00:00:00 Paul Berg introduces the public policy debate around the beginnings of the field in the 1970s.

00:00:30 As some of you are aware, the chemical sciences in North America got their organized start

00:00:57 in 1765, when Benjamin Rush became the first professor of chemistry on the North American continent, just three blocks from where we are today.

00:01:09 So this is a wonderful place to be exploring and celebrating some of the most recent developments in the molecular field.

00:01:22 The purpose of the Chemical Heritage Foundation is to record and make known the story of the chemical and molecular sciences.

00:01:33 And today we're fundamentally doing the first of those tasks. We are recording.

00:01:39 As you can see, this is an event that's being put onto archival videotape.

00:01:45 And then in due course, we shall make excerpts from that tape for use in school and other contexts.

00:01:52 Because this is a video event, we'd be grateful if you could restrict your coming and going to the actual breaks in the program.

00:02:02 There's a mid-morning break at 10.45, there's a luncheon break and lunch is here in the building, and there's a mid-afternoon break.

00:02:11 And now, without more ado, I'll hand over to the moderator of the event, a distinguished Harvard professor, Everett Mendelsohn. Everett?

00:02:21 Arnold, thank you very much for opening.

00:02:25 And I would really want to say a word of thanks for those of us who do the history of science and those who've done the science whose history we're looking at.

00:02:33 Thanks to you, Arnold, and the Chemical Heritage Foundation for stepping out front and trying still another way to look at history and to do history.

00:02:45 Not to make history, we'll hear about that soon, but to do what historians do.

00:02:50 Some years ago, I think at about 20, and Charles can bring me up to date, a group of physicists, theoreticians, machine builders, instrument makers,

00:03:02 and historians got together at the American Academy of Arts and Sciences to talk about the doing of their history.

00:03:11 And it was a fascinating occasion. Think of Emilio Segrè and L. M. Stanley Livingston, the machine builder and the theoretician,

00:03:21 at one level talking right past each other, but at another level talking about exactly the same thing.

00:03:27 It was all taken down, typed out, and it's in somebody's bottom drawer.

00:03:35 Similarly, perhaps learning from that a bit, some years later, John Etzel and Joseph Frouton and a number of us began bringing together

00:03:45 some of the people engaged in the early work in the history of biochemistry and molecular biology together with historians.

00:03:51 And out of that came that marvelous collection of manuscripts, letters, housed right here at the American Philosophical just a few blocks from where we're meeting today.

00:04:02 But it, too, was on paper, on film. And what we're turning to today, the aim of this session, is really to do history, not through books,

00:04:13 but to get people who were involved in the activities themselves to explain themselves to an audience like the one before us,

00:04:22 but then also to each other, so that they can exchange and share their own sense of what their history was about.

00:04:30 I hope that as the day goes on, they'll question each other, they'll correct each other, they'll comment on each other,

00:04:36 and we'll gain a cumulative sense of what was going on. Our strategy is straightforward.

00:04:43 This morning, we'll have a series of presentations, 20 minutes each, by some of the key figures in the making of modern molecular biology and biotechnology.

00:04:57 From the laboratory bench, to the factory, to the distribution of products around the world.

00:05:05 In the afternoon, we will entertain questions and comments, questions and comments which you will have generated.

00:05:13 In your folder, each of you has a sheet in which we ask you to write down a question, a comment, probe hard.

00:05:21 Over the lunch hour, we'll take those and see if we can bring together a series of coherent, focused attempts to elucidate elements,

00:05:29 to question, to probe what it is that our panelists, distinguished panelists, have talked about.

00:05:37 And they will join the discussion with each other.

00:05:39 So the morning presentation, the afternoon discussion and question.

00:05:43 Be sure to write down your questions and your observations.

00:05:46 Hand them in on the way out to our associates who will be at the two doors.

00:05:51 Without further ado, and without presenting long introductions, you've each got in your program fine introductions of our panelists.

00:06:00 Let me call on Charles Weiner, a colleague in the history of science from Massachusetts Institute of Technology,

00:06:06 who had the advantage of being one of the first people to begin collecting the documents and recording elements

00:06:12 in one of the challenging periods of the making of biotechnology.

00:06:16 Charles Weiner.

00:06:23 The program says that I'll give the big picture.

00:06:25 I think I've been framed.

00:06:27 It's a long story and a rich and interesting one, and we have very little time to deal with it.

00:06:33 But what an interesting and exciting opportunity we have today.

00:06:38 And yet, what a daunting task.

00:06:40 We're exploring the history of a profound intellectual and social transformation of the life sciences.

00:06:48 It involves dramatic changes in the ideas, concepts, and techniques, in the technologies and industries,

00:06:57 in the institutions, government, universities, and in the policies,

00:07:05 and in the public perceptions and expectations regarding the use of this knowledge,

00:07:11 and especially in the roles of biologists in the field.

00:07:17 The roles as researchers, as entrepreneurs, as educators, as lobbyists, and critics.

00:07:23 All of these components are intertwined and connected like the strands of the double helix.

00:07:31 And today, we'll try to unravel some of that.

00:07:35 Fortunately, for all of this, we're limiting our probes to the three decades

00:07:39 since the illumination of the double helical structure of the DNA molecule in 1953.

00:07:47 This period, the 30 years that we'll cover, the three decades approximately,

00:07:51 has often been heady with success, and at times frustrating,

00:07:56 uncertain, and unsettling for many of the participants, and always controversial.

00:08:03 There's a lot to explore here in less than a total of six hours of talk,

00:08:08 so we should be modest in our expectations.

00:08:11 And the aim as Everett Mendelsohn is not to write history,

00:08:15 but to provide testimonies about the personal experiences, the perceptions,

00:08:19 and insights of some of the individuals who've played key roles in these developments.

00:08:25 There's already a rich literature on the history of these events,

00:08:29 including scholarly works by historians based on archival sources,

00:08:33 autobiographical memoirs by scientists in the field,

00:08:37 reviews by political analysts, popular accounts by science writers,

00:08:41 and even novels or near-novels.

00:08:45 On the subject, two titles come to mind,

00:08:49 one at the beginning of the period by James Watson,

00:08:51 The Double Helix, sort of a memoir-cum-novel,

00:08:55 which describes the efforts to understand the structure of DNA,

00:09:00 and another at the end of the period, published in 1983,

00:09:04 a real novel called Spirals,

00:09:08 which is set in the context of the Cambridge, Massachusetts,

00:09:12 recombinant DNA safety controversy.

00:09:14 It's sort of a genetic engineering medical horror story.

00:09:20 They're very valuable,

00:09:24 also untapped, or only partially tapped,

00:09:28 resources in this area, as was previously mentioned,

00:09:32 and there are current projects at the University of California

00:09:36 in San Francisco to document the development

00:09:40 of biochemistry in California,

00:09:44 and today we'll also do a good deal of that,

00:09:46 because the panel is heavily weighted with California participants,

00:09:50 although four, including myself,

00:09:54 started out in the same corner of Brooklyn, New York,

00:09:58 which was a while back.

00:10:04 What we can do here today

00:10:08 is juxtapose the partial perspectives

00:10:12 of participants and observers,

00:10:16 and in this juxtaposition, we can develop resources

00:10:20 for historical study.

00:10:22 So what's happened? What's so dramatic

00:10:26 about this period from the double helix structure to the early 80s?

00:10:30 What changed? The science changed, the scientists,

00:10:34 the relationships among universities, government, and industry,

00:10:38 the place of molecular genetics in culture,

00:10:42 and the ethical and social consequences of research and applications.

00:10:46 I can only provide highlights in a small amount of time

00:10:50 with perhaps somewhat more emphasis on the social, ethical, and political dimensions,

00:10:54 and a focus of my own historical research and first-hand observation

00:10:58 as a witness to some of these changes.

00:11:02 When Watson and Crick identified the precise double helix molecular structure

00:11:06 of DNA in 1953, it was clear to them and to the thrilled scientists

00:11:10 who read their paper that it could illuminate how

00:11:14 hereditary information was stored in DNA,

00:11:18 how it could be replicated and mutated, and how it could be transformed

00:11:22 when necessary to make a variety of different proteins.

00:11:26 DNA came to be seen by the scientists as the master

00:11:30 molecule of life.

00:11:34 The ongoing work in the biochemistry of nucleic acids,

00:11:38 which was pursued in the laboratories of Ochoa,

00:11:42 Kornberg, and Karana, received new attention

00:11:46 as a result, and when in 1955, Kornberg

00:11:50 and his colleagues isolated an enzyme that in principle could synthesize DNA

00:11:54 in vitro, it demonstrated that the artificial synthesis of genes

00:11:58 would be possible. Other important work in the U.S.

00:12:02 and Europe shed light on the genetic mechanisms of bacteria and viruses.

00:12:06 Feeberish work in the 1960s

00:12:10 in a number of laboratories resulted in the complete cracking of the genetic code

00:12:14 by 1968.

00:12:18 The information and techniques for genetic engineering and genetic

00:12:22 manipulation were amassing, including the isolation of a

00:12:26 bacterial gene, in vitro synthesis of

00:12:30 viral DNA, the work on restriction enzymes which could

00:12:34 cut DNA in specified, precise locations,

00:12:38 and the transfer of drug resistance in plasmids.

00:12:42 Scientists' interest in genetic engineering increased,

00:12:46 with the concern of many of them about its ethical implications and appropriate limits.

00:12:50 When and where to draw the line in the potential

00:12:54 applications of human genetic engineering was a major subject

00:12:58 of scientific and public discussion in the 1960s.

00:13:02 This was before the recombinant DNA techniques.

00:13:06 Discussion of the prospects for human genetic intervention overflowed

00:13:10 from scientific meetings to the media and to Congress,

00:13:14 and some biologists began to worry about losing control of the discussions.

00:13:18 They feared that public overreaction

00:13:22 would interfere with their research interests and their funding, and they tried

00:13:26 to reassure the public that the work would be beneficial, or

00:13:30 that it was too early to worry about possible negative effects.

00:13:34 Others argued that the possible negative

00:13:38 consequences of genetic engineering, the ethical issues, should be

00:13:42 anticipated and discussed and advanced before it was too late,

00:13:46 as in the case of the atomic bomb.

00:13:50 That was very popular imagery in the period. The image of the mushroom cloud was

00:13:54 frequently linked to the potential hazards

00:13:58 of the DNA double helix. Two symbols of that

00:14:02 time. The point was that

00:14:06 prior discussion provided time to think about the issues

00:14:11 before technological momentum built up

00:14:15 and applications were imminent, and before vested interests

00:14:19 would take over. The concerns of the period

00:14:23 emerged into the political process in 1968,

00:14:27 when a series of hearings were initiated in the United States Senate.

00:14:31 The point was to consider the need for a

00:14:35 national commission to anticipate and to examine

00:14:39 in advance a variety of biomedical

00:14:43 research, the ethical, legal, and social problems

00:14:47 possibly connected with it, and that included genetic engineering.

00:14:51 It was meant to be a study commission without

00:14:55 the intention of interfering with research. The focus was on new

00:14:59 emerging medical technologies such as the artificial heart, organ transplants,

00:15:03 new reproductive technologies, and genetic engineering,

00:15:07 which was not possible but certainly on the horizon.

00:15:11 As you can understand, all of those issues are still with us.

00:15:15 The biologists who participated in the hearings expressed a variety of

00:15:19 views. There were genuine concerns about the issues raised,

00:15:23 there was a fear that their funding might be cut off or severely curtailed,

00:15:27 there was defensiveness about the nature and the usefulness

00:15:31 of the work, and worry that what some scientists

00:15:35 felt as public intervention in the scientific process

00:15:39 would interfere with their work

00:15:43 of which they would no longer have control. Several of them tried to reassure

00:15:47 Congress by arguing that concerns about human genetic intervention

00:15:51 were premature and that it was too early to deal with them.

00:15:55 Some pointed to several immediate visible problems

00:15:59 arising from new medical interventions, including the protection of human subjects in research,

00:16:03 and maintained that they were more worthy of concern than

00:16:07 the future applications of genetics in

00:16:11 these fields. While congressional action

00:16:15 to anticipate and study the ethical implications of genetic engineering

00:16:19 faded in the early 1970s, the new recombinant DNA

00:16:23 techniques were being invented.

00:16:27 The development of these techniques

00:16:31 and we'll hear more about it later,

00:16:35 the work of Paul Berg, Loban Kaiser,

00:16:39 of Herb Boyer, of Stanley Cohen, and Annie Chang,

00:16:43 the latter work on plasmids,

00:16:47 all of this work together was a major event in the history

00:16:51 of science. It was the result of decades of fruitful research in many

00:16:55 countries, most of it supported by government

00:16:59 support, particularly large sums from the National Institutes of Health in the

00:17:03 United States. These techniques involve the use of the newly discovered

00:17:07 restriction enzymes to isolate and remove specific

00:17:11 gene sequences from DNA molecules of various organisms.

00:17:15 They also involve the application of methods to reproduce

00:17:19 large amounts of exact copies of the hybrid or recombinant

00:17:23 DNA molecules. The ability to manipulate

00:17:27 nucleotide sequences directly

00:17:31 made it possible to transmit genetic information among different

00:17:35 species. That provided a powerful tool for the study

00:17:39 of the structure and function of genes and made it possible to study

00:17:43 details of DNA and its transcription in cells of higher organisms.

00:17:47 It was now possible to ask questions that previously

00:17:51 couldn't have been answered and in fact to get the answers.

00:17:55 The biologists immediately recognized the major significance of these developments.

00:17:59 They were now able to solve problems at the forefront of knowledge

00:18:03 which also had possible important applications and it was apparent to them

00:18:07 from the start that that would be the case.

00:18:11 In 1973, at the Gordon Conference on

00:18:15 Nucleic Acids, which was co-chaired by Maxine Singer,

00:18:19 some of these results were reported

00:18:23 by Herbert Boyer. Scientists there were

00:18:27 excited and some of them also expressed concern about the

00:18:31 possible laboratory safety hazards associated with the research

00:18:35 being launched. A letter from the participants of the meeting

00:18:39 led the National Academy of Sciences to set up a committee

00:18:43 chaired by Paul Berg and that committee

00:18:47 after a meeting at MIT in 1974

00:18:51 issued a letter to be published to the scientific community

00:18:55 calling attention to the potential of these new techniques

00:18:59 their new power and also about the possible safety hazards.

00:19:03 They urged colleagues to avoid

00:19:07 certain experiments which were considered to be potentially hazardous

00:19:11 until such time that scientists could be assembled

00:19:15 six months later at a conference to assess these hazards

00:19:19 to see what existed and to devise a framework to minimize

00:19:23 any possible risk to laboratory workers or to the public.

00:19:27 So they were concerned with the potential hazards.

00:19:31 That conference, the February 1975 Asilomar Conference, brought together

00:19:35 scientists in the field and they considered

00:19:39 the information that they had then about the hazards.

00:19:43 The remarks at the opening of the conference, which is

00:19:47 on tape at the MIT

00:19:51 Recombinant DNA History Collections and also at the

00:19:55 National Academy of Sciences, gives a little spirit of the meeting.

00:19:59 David Baltimore gave the introductory remarks. He was one of the

00:20:03 meeting's organizers and I'll quote a brief part of his statement.

00:20:07 The issue that brings us here is the new technique of molecular

00:20:11 biology appears to have allowed us to outdo

00:20:15 standard events of evolution by making combinations

00:20:19 of genes which could be immediate natural history.

00:20:23 These pose special potential hazards while they offer

00:20:27 enormous benefits. We are here to balance the

00:20:31 benefits and hazards and to design a strategy which will maximize the benefits

00:20:35 and minimize the hazards for the future. Now that the tools

00:20:39 for genetic manipulation were available, the concerns of the

00:20:43 researchers were narrowed to the immediate technical problems of laboratory

00:20:47 safety and they developed technical solutions to these problems.

00:20:51 The long-term ethical consequences discussed in the earlier period

00:20:55 before these tools were available, the consequences of possible

00:20:59 applications of genetic manipulation were deferred once again.

00:21:03 The recombinant DNA scientists'

00:21:07 own concern about laboratory safety

00:21:11 had initiated public scrutiny of the new research. And this was

00:21:15 emphasized by local hearings in a number of communities where academic groups

00:21:19 were tooling up to do inquiries into this field of research.

00:21:23 That's Cambridge, San Diego, Ann Arbor, New Haven,

00:21:27 Princeton, and many other communities. Followed by the late

00:21:31 1970s by the introduction of 16 separate bills

00:21:35 in Congress to regulate recombinant DNA safety standards.

00:21:39 In most cases to apply the NIH guidelines.

00:21:43 Research universities and scientific organizations were worried about public

00:21:47 overreaction, as they saw it, and about losing control of the decisions regarding

00:21:51 work in their laboratory. And scientists

00:21:55 involved in the controversy vigorously resisted local and national

00:21:59 legislation that would have made the NIH laboratory

00:22:03 safety guidelines mandatory. Several prominent biologists

00:22:07 who had shared the early concern about the hazards, the potential hazards,

00:22:11 publicly recanted, saying that they had overstated

00:22:15 the risks and now could provide reassurance

00:22:19 that the work was safe. In the end, no legislation was

00:22:23 passed by Congress. And by 1979, the NIH

00:22:27 recombinant DNA guidelines had been made far more permissive

00:22:31 than the original 1976 version. More than

00:22:35 90% of the United States research in the field was either no longer covered by

00:22:39 the guidelines or was subject to only minimal controls equivalent

00:22:43 to standard laboratory practice.

00:22:47 Well, what happened then? The recombinant DNA techniques

00:22:51 and the new methods of cell fusion, rapid DNA sequencing

00:22:55 and other important approaches and technologies

00:22:59 had an enormous scientific and social impact.

00:23:03 They made possible new research in the structure and function of genes.

00:23:07 They opened up entire new fields of inquiry and led to a variety

00:23:11 of applications in industry, agriculture, and medicine. Biology had been

00:23:15 transformed, and so had been the biologists.

00:23:19 Very rapidly in the early 1980s, academic biologists, never

00:23:23 before involved with industry, became consultants, advisers,

00:23:27 founders, equity holders, and contractees

00:23:31 of new biotechnology firms or new divisions of multinational

00:23:35 corporations.

00:23:39 Just a few words about the effects on university

00:23:43 industry relations and the important changes.

00:23:47 In 1974, two university biologists,

00:23:51 Stanley Cohen and Herbert Boyer,

00:23:55 were requested by Stanford University to file

00:23:59 a patent on the recombinant DNA techniques with the

00:24:03 income, if the patent was granted and made any money, the income to go to the university.

00:24:07 The Supreme Court in 1980

00:24:11 came up with a decision on a

00:24:15 very close vote from 5 to 4, but nevertheless a decision

00:24:19 to allow the patenting of what they called man-made organisms

00:24:23 under specific

00:24:27 categories. Congress, and they said that Congress

00:24:31 if they had any objection to it, could pass laws about it.

00:24:35 Congress, in fact, encouraged the commercialization of

00:24:39 university research supported by public funds through legislation

00:24:43 that would make it easier for universities to patent

00:24:47 the results of federally funded research.

00:24:51 By 1980, about 100 United States firms were estimated to be

00:24:55 evaluating or conducting recombinant DNA or other

00:24:59 biotechnology research.

00:25:03 The academic researchers who became involved

00:25:07 underwent almost an overnight transformation.

00:25:11 My experience, particularly in California where I spent

00:25:15 time going from laboratory to laboratory, was that there was

00:25:19 a great deal of confusion and concern about

00:25:23 what this meant in terms of the restraints

00:25:27 on the sharing of information. There were specific complaints

00:25:31 that cell lines, plasmids, bacterial strains

00:25:35 were not circulating freely, and that information, which was

00:25:39 informal information, which was the lifeblood of scientific advance

00:25:43 was being inhibited. Others said, oh, this is just

00:25:47 early, you'll get used to it, and things will calm down.

00:25:52 Because of the limit in time,

00:25:56 this history of the world

00:26:00 can only go on for a brief moment.

00:26:04 What happened was that the attitudes

00:26:08 in universities, which first started out by university presidents

00:26:12 talking and some leading biologists talking about the intrusion of commerce

00:26:16 in this field into the university and the effect on

00:26:20 scholarship, the effect on the environment and the institution,

00:26:24 that changed by the latter part of the period

00:26:28 of the 80s to universities aggressively pursuing

00:26:32 their faculty to patent, and in fact, universities setting up

00:26:36 their own firms in order to become involved and profit from the

00:26:40 biotech revolution. These were very difficult and interesting

00:26:44 times, so let me just summarize in the statement

00:26:48 of the biologist that I interviewed, an academic biologist,

00:26:52 who in 1983 had attended a

00:26:56 small meeting on the prospects for human genetic intervention,

00:27:00 and I asked him why there was so

00:27:04 little time for discussion at that meeting

00:27:08 of the ethical implications, since that had been

00:27:12 an important thing in the past. They were talking

00:27:16 specifically about the prospects for human gene therapy, and he answered this,

00:27:20 expressing some of the dilemma.

00:27:24 I wanted more discussion on the ethical issues. I did, and I didn't.

00:27:28 There's a sense in which it's more fun to talk about the science.

00:27:32 You're actually doing things in science.

00:27:36 I think everyone who lived through the Asilomar period in the late 70s and the

00:27:40 regulatory period came to recognize that at the end of the day, when you're working

00:27:44 on scientific things, you're in control. You, yourself,

00:27:48 are in control of what you're doing, of your laboratory,

00:27:52 or of your scientific environment. When you get involved in regulatory,

00:27:56 ethical, or political issues, you have to share that control, and often

00:28:00 you have very little input into what happens. I think that scientists like being

00:28:04 in control. I think all of us find such situations at best

00:28:08 ambiguous, and at worst profoundly unsettling.

00:28:12 So, with those words which characterize the end

00:28:16 of this period that we're dealing with in the early 80s,

00:28:20 I'd like to stop and have an opportunity

00:28:24 to hear the testimonies of others who were

00:28:28 involved in those events. Thank you.

00:28:32 Charlie, thank you very much

00:28:36 for putting in perspective some of the elements

00:28:40 which we'll hear more about in the coming talks.

00:28:44 Arthur Kornberg, our next presenter,

00:28:48 was truly present at the beginning. As Charles mentioned

00:28:52 in his own presentation, Arthur Kornberg's work in the

00:28:56 early stages of biochemistry and molecular biology coming together in the post-war

00:29:00 period was absolutely essential for some of the elements

00:29:04 that went on to make up the basis of the current

00:29:08 work in the field. He comes from Stanford University,

00:29:12 where a substantial part of the important work was done, but he's also

00:29:16 had deep industrial involvement. His scientific work was recognized

00:29:20 by a Nobel Prize in 1959. Arthur Kornberg.

00:29:24 Arthur Kornberg.

00:29:36 Thank you, Everett, and thank you, Arnold Thackeray,

00:29:40 and the Foundation, for initiating

00:29:44 and organizing this effort to record

00:29:48 all histories of some of us who contributed

00:29:52 to the emergence of biotechnology.

00:29:56 Now, histories of science commonly start with the Greeks

00:30:00 and they end with

00:30:04 Darwin and Newton, so I am pleased that

00:30:08 records are being assembled here to chronicle recent

00:30:12 events in what I also regard as the most

00:30:16 revolutionary advance in the history of

00:30:20 biological and medical sciences.

00:30:24 Yet, it's an exercise in history, and we're aware

00:30:28 that our accounts today will likely differ in substance,

00:30:32 surely in emphasis, and that illustrates

00:30:36 the Rashomon effect, that the past, like the future,

00:30:40 is uncertain.

00:30:44 My assignment is to discuss the science, and this very

00:30:48 brief review of the scientific foundations of biotechnology.

00:30:52 I will not cite the numerous contributions

00:30:56 from chemistry, biochemistry, microbiology, genetics.

00:31:00 These can be found in several books and reviews, and you've heard an excellent

00:31:04 brief review from Charles Weiner, and Stanley

00:31:08 Cohn, who will follow me, will surely discuss the major role of

00:31:12 microbiology, plasmidology. Also,

00:31:16 I won't conform to the common view that it all started

00:31:20 with the Watson-Crick model of DNA. Instead,

00:31:24 I want to go back a hundred years to celebrate

00:31:28 the centenary this very year of what I regard

00:31:32 to be the birth of modern biochemistry.

00:31:36 1897 was a big year for science.

00:31:40 J.J. Thomson discovered the electron,

00:31:44 and with the numerous and momentous advances in physics around the turn

00:31:48 of the century, ushered in the golden

00:31:52 half-century of modern physics. In 1897,

00:31:56 C.W. Post introduced grape nuts,

00:32:00 a cereal without grapes or nuts,

00:32:04 but it also revolutionized breakfasts around the world.

00:32:08 It was also in 1897 that

00:32:12 Edouard Buchner accidentally observed

00:32:16 that a yeast juice could convert sucrose to ethanol,

00:32:20 and this discovery disposed of a firm

00:32:24 belief, propagated by Louis Pasteur,

00:32:28 that alcohol fermentation is a vital operation of an intact

00:32:32 cell, and thus Buchner's discovery

00:32:36 was the origin of modern biochemistry

00:32:40 because it preceded and initiated 40 years of

00:32:44 enzyme fractionation that resolved this so-called

00:32:48 zymase activity into a dozen discrete

00:32:52 molecularly defined reactions. And with the

00:32:56 reconstitution of alcoholic fermentation, incidentally

00:33:00 a phenomenon that baffled scientists for a couple of centuries,

00:33:04 was then explained in molecular terms, and the stage was set

00:33:08 for the extraordinary advances of biomedical science

00:33:12 that we've witnessed in the last half of our century.

00:33:16 Now during the course of resolving the alcoholic fermentation

00:33:20 in yeast juice, glycolysis,

00:33:24 the conversion of glycogen to lactic acid by a muscle

00:33:28 extract, also resolved into its molecular components,

00:33:32 was astonishingly, almost virtually

00:33:36 identical to the yeast pathway.

00:33:40 And so we witnessed that the conservation

00:33:44 of mechanisms and molecules for a billion

00:33:48 or more years of evolution, witnessed in

00:33:52 bacteria, fungi, plants, and animals,

00:33:56 has been conserved to this

00:34:00 extraordinary extent, and even further in a number of bioenergetic

00:34:04 and biosynthetic pathways. And I regard this

00:34:08 universality of biochemistry as one of the great revelations

00:34:12 of our century. Attention to

00:34:16 enzymology and biochemistry has been diminished in recent

00:34:20 decades by the advent of molecular biology.

00:34:24 And because of this, it is worth noting what these

00:34:28 classic disciplines have provided conceptually

00:34:32 and practically to the emergence of biotechnology.

00:34:36 Enzymology solved chemical and biological problems.

00:34:40 It made available the reagents for recombinant DNA

00:34:44 and genetic engineering. And it encouraged reliance

00:34:48 on the universality of biochemistry

00:34:52 that's been exploited for gene expressions

00:34:56 at various gene factories.

00:35:00 That enzymology can solve chemical and biological

00:35:04 problems is based on the fact that virtually all

00:35:08 biologic operations are catalyzed, directed,

00:35:12 regulated by enzymes. Spontaneous

00:35:16 reactions in cells do not occur, if so,

00:35:20 very rarely. Witness the hydration of carbon dioxide

00:35:24 depends on carbonic anhydrase. Melting of

00:35:28 DNA, a spontaneous reaction, is catalyzed by a variety

00:35:32 of helicases. Hybridization of DNA, commonly practiced,

00:35:36 is facilitated by DNA binding proteins.

00:35:40 Now, whereas organic chemists were reluctant to recognize,

00:35:44 let alone use enzymes, Gobin-Kurana,

00:35:48 by exploiting this awesome specificity and catalytic efficiency

00:35:52 of enzymes, achieved the first total synthesis of a gene,

00:35:56 the gene for alanine tRNA.

00:36:00 And in the epical paper by Watson and Crick, the only flaw

00:36:04 I can find is their suggestion that

00:36:08 nucleotides aligned by base pairing to a DNA

00:36:12 template would polymerize spontaneously.

00:36:16 Now, to reduce a biologic event to molecular detail,

00:36:20 the enzymologist must first observe it in a cell-free system

00:36:24 and then resolve and reconstitute the event.

00:36:28 And beyond the classic examples that I've cited of alcoholic fermentation,

00:36:32 the synthesis and utilization of glycogen,

00:36:36 more recent such examples are the

00:36:40 elucidation of gene expression, replication, repair,

00:36:44 recombination of DNA. The biologic event can actually

00:36:48 be performed even better by the biochemist than by the cell.

00:36:52 The cell is constrained with having

00:36:56 to provide a consensus medium for thousands of diverse reactions.

00:37:00 So by saturating the enzyme with its substrate,

00:37:04 trapping the products, and providing optimal

00:37:08 pH, salt, ionic conditions, metal ions, and so forth,

00:37:12 the biochemist gains a more precise understanding of the enzymes,

00:37:17 the mechanisms, the pathways, and their ultimate

00:37:21 relation to physiologic events.

00:37:25 Now, as a case study, I'd like on this occasion to consider

00:37:29 the discovery of DNA polymerase in an extract of E. coli.

00:37:33 It might be assumed, and in fact has been on occasion,

00:37:37 that the Watson-Crick model in 1953

00:37:41 spurred me to search for the enzymes of replication.

00:37:45 But that is not the way it happened. DNA did not

00:37:49 become the center of my interests. In the preceding

00:37:53 years, I had studied a humble enzyme,

00:37:57 nucleotide pyrophosphatase from potatoes.

00:38:01 And then I had found products of that reaction which opened the way

00:38:05 for me to explore the biosynthesis of coenzymes and

00:38:09 nucleotides. And this, in turn, awakened

00:38:13 my interest in how these nucleotides might be assembled

00:38:17 into DNA and RNA. At that time, we lacked

00:38:21 the knowledge of what the true building blocks of nucleic acids

00:38:25 were. And so I first exploited the biosynthetic

00:38:29 pathways of the purines and pyrimidines. And from these studies, I found

00:38:33 that it was the 5' substituted nucleotide to be

00:38:37 the prime product and the likely precursor of nucleic acids.

00:38:41 What led me then to DNA replication

00:38:45 was an unremitting fascination with enzymes.

00:38:49 And we found a few counts of C14

00:38:53 thymidine incorporated into an acid-insoluble

00:38:57 DNA-sensitive form

00:39:01 by an extract, a very crude extract, of E. coli.

00:39:05 It was a tiny wedge, but the hammer

00:39:09 was enzyme fractionation. We had added

00:39:13 calf thymus DNA along with this labeled thymidine

00:39:17 and then learned that the DNA provided

00:39:21 both the primer chains for extension by nucleotides

00:39:25 and we intended it to be a pool to shield any

00:39:29 DNA we might make from the degradation by nucleic acids.

00:39:33 But the DNA also proved to be the source

00:39:37 of the then unknown A, T, G, and C

00:39:41 deoxynucleotides. And most gratifying,

00:39:45 the DNA still had another function. It served as a

00:39:49 template to direct polymerase in assembling

00:39:53 a precise arrangement of DNA as

00:39:57 exemplified in a DNA chain.

00:40:01 Such a directed action by a substrate

00:40:05 to direct an enzyme was unprecedented in enzymology.

00:40:09 And in the course of purifying and isolating the DNA

00:40:13 polymerase, we had to discover and purify out of

00:40:17 the E. coli extract seven other enzymes,

00:40:21 including the kinases that activated the thymidine and the

00:40:25 four deoxynucleoside mono and diphosphates.

00:40:29 From 1956 on, I tried repeatedly

00:40:33 with no success to show biologic activity

00:40:37 for the products of this polymerase action, using

00:40:41 DNA templates from a variety of sources, bacteria such as

00:40:45 pneumococcus, haemophilus, B. subtilis. And finally,

00:40:49 after more than ten years of trying, in 1967,

00:40:53 with the discovery that year of DNA ligase

00:40:57 that seals chains, done incidentally by four groups independently,

00:41:01 we had the reagent that enabled us to

00:41:05 replicate the single-stranded circle of a small phage DNA

00:41:09 called Phi X. The polymerase product

00:41:13 was fully infectious as the virus itself.

00:41:17 And when that result was announced, it was widely

00:41:21 interpreted by the media as, quote, creation of life

00:41:25 in the test tube. It was a news event, which

00:41:29 in a very small dimension, like the cloning of a sheep dolly.

00:41:33 Now the reactions of scientists, however,

00:41:37 were far more muted. Most had anticipated the result.

00:41:41 Why'd it take so long to get it? And some were vocally

00:41:45 doubtful of the practical value of this particular result.

00:41:49 And yet I'd like to take this occasion to point out the implications

00:41:53 which do have, or did have then, genuine significance.

00:41:57 For one, a genome of

00:42:01 5,386 nucleotides had been faithfully

00:42:05 replicated. For another, the building blocks

00:42:09 we used were synthetic, the four synthetic deoxynucleoside

00:42:13 triphosphates. There were no novel building blocks needed,

00:42:17 nor were there any linkages other than the standard phosphodiester

00:42:21 backbone of DNA. And furthermore,

00:42:25 we now had the ability to introduce specific

00:42:29 mutations into a viral genome. And I

00:42:33 used the term genetic engineering in a lecture a few months later

00:42:37 in 1968 to denote such potential

00:42:41 applications. And I recall being admonished after that lecture, it was given

00:42:45 at Boston University in St. Louis, to refrain from using

00:42:49 the term genetic engineering. It had a bad ring to it, I was told.

00:42:53 And so now we've adopted biotechnology as a

00:42:57 euphemism. Now in addition to clarifying

00:43:01 mechanisms and metabolic pathways, these purified

00:43:05 enzymes also provided unique, analytic

00:43:09 and preparative reagents. And during the decades of

00:43:13 the 50s and 60s, powerful new methods of enzyme

00:43:17 purification and criteria for homogeneity of enzymes

00:43:21 developed. And subsequently, the availability of gene cloning

00:43:25 over expression made it even easier to obtain

00:43:29 large quantities of purified enzymes.

00:43:33 Now with the enzyme as a reagent,

00:43:37 a substrate could be measured definitively and precisely.

00:43:41 A product of the enzyme reaction, previously unavailable

00:43:45 could be made in abundance isotopically labeled.

00:43:49 And in the course of purifying an enzyme, new enzymes

00:43:53 and reagents were discovered. The fractionation of DNA

00:43:57 polymerase disclosed exonuclease 3

00:44:01 and later on, homogeneous polymerase was found to have

00:44:05 two distinctive entities within its chain.

00:44:09 One that degraded DNA from 3 to 5, another from 5

00:44:13 to 3. Nick translation, in which the synthetic

00:44:17 activity of the polymerase is coordinated with these exonuclease activities

00:44:21 proved in the 1960s to be the favored

00:44:25 means of preparing highly radioactive DNA.

00:44:29 Now this polymerase, along with ligase that

00:44:33 seals DNA chains, and other enzymes

00:44:37 terminal transferase, exonucleases,

00:44:41 these provided the reagents that Paul Berg and the Loeb and Kaiser groups

00:44:45 at Stanford used to add sticky

00:44:49 tails to DNA chains in order to make the first

00:44:53 recombinant DNA. Bob Lehman's lab, my lab

00:44:57 provided advice on how to use these enzymes as well as

00:45:01 making them available. The discovery by Hamilton Smith

00:45:05 and Dan Nathans of the actions of restriction nucleases

00:45:09 and their remarkable capacities to cleave DNA

00:45:13 in specific sequences, including some that

00:45:17 create overlapping sticky ends, provided a better

00:45:21 way to align unrelated DNA strands in making

00:45:25 hybrid recombinant DNAs. Now I've given

00:45:29 great emphasis to enzymology as one of the foundations

00:45:33 of genetic engineering and associated biotechnologies.

00:45:37 I'd be remiss if I failed to mention that many other

00:45:41 disciplines and achievements contributed to the mammoth

00:45:45 biotechnology enterprise that inspired this symposium.

00:45:49 Now among the foremost is microbial genetics

00:45:53 and physiology, including the phages, bacterial viruses,

00:45:57 and plasmids that serve as vectors.

00:46:01 These are genomes, windows on microbial events.

00:46:05 A crucial contribution, often ignored,

00:46:09 was that of Mort Mandel, who provided a recipe

00:46:13 for making E. coli accessible to DNA or plasmids

00:46:17 and thus made it a favored host for

00:46:21 expression of genes. Still other major advances have been

00:46:25 in DNA chemistry, the sequencing of DNA,

00:46:29 synthesis of oligonucleotides, and the DNA amplification

00:46:33 by PCR, which made use of DNA enzymes,

00:46:37 incidentally, either directly or tangentially.

00:46:41 Finally, I want to comment once again, especially on this

00:46:45 occasion, on the universality of biochemistry,

00:46:49 particularly the remarkable uniformity of genetic codes

00:46:53 and their expression. Despite confidence in this

00:46:57 universality, few of us, and I include myself,

00:47:01 anticipated that E. coli would be so permissive and

00:47:05 responsive in expressing eukaryotic genes

00:47:09 and so lead to the accumulation of massive amounts

00:47:13 of their products. And on a social note,

00:47:17 we need to be reminded that the science that

00:47:21 undergirded biotechnology, the source of its

00:47:25 practitioners, is owed entirely to academic

00:47:29 laboratories, supported almost entirely by NIH

00:47:33 institutions. How appropriate it would be

00:47:37 for biotech ventures or pharmaceutical industry

00:47:41 to repay a basic debt

00:47:45 that they owe to basic science, not only as they have

00:47:49 already with technological advances, but also to

00:47:53 join in strenuous efforts to strengthen federal

00:47:57 budgets for support of the available talent

00:48:01 and creativity we have to discover the utterly novel

00:48:05 technologies needed to advance science

00:48:09 and propel industry to provide the

00:48:13 substance for what I hope will be future meetings

00:48:17 of the Chemical Heritage Foundation. Thank you.

00:48:31 Arthur Kornberg, thank you very much for that fine

00:48:35 path through a series of

00:48:39 steps which have often been left out by others in understanding

00:48:43 the emergence of molecular biology and biotechnology, and I know

00:48:47 we'll come back to some of the issues you raised in this afternoon's discussion.

00:48:51 Stanley Cohen is another contributor

00:48:55 from Stanford University. His work on plasmids was a key element

00:48:59 in recombinant DNA work, being referred to by many as the

00:49:03 basis of the new genetics. He's recipient of both the National

00:49:07 Medal of Science and the National Medal of Technology. Stanley Cohen.

00:49:17 Thank you very much. I'd like to thank the organizers for inviting

00:49:21 me to this meeting. Let me start by

00:49:26 pointing out that in the Japanese film classic, Rashomon,

00:49:30 mentioned by Arthur Kornberg at the start of his talk, the same events

00:49:34 are perceived quite differently by three different individuals, and there's no way

00:49:38 for an involved person, for an uninvolved person, to determine which

00:49:42 perception is actually correct. While the history of recombinant

00:49:46 DNA has also been told differently by different persons,

00:49:50 there is, in this instance, a documentable series of events

00:49:54 that transcend varying perceptions, assertions,

00:49:58 and oral history recollections. There's the perception of history,

00:50:02 but there's also the actual history. I'd like to

00:50:06 spend the next 20 minutes recounting some of the events that

00:50:10 led to the invention of recombinant DNA, as well as my views

00:50:14 about their significance. The term recombinant DNA was

00:50:18 introduced in a paper my colleagues and I published in early 1974.

00:50:22 It was intended to be synonymous with DNA cloning.

00:50:26 However, recombinant DNA has also been used in a narrower sense, as we've

00:50:30 just heard in Arthur Kornberg's talk, to refer to composite

00:50:34 DNA molecules that result from the physical joining

00:50:38 of DNA fragments in a test tube. In reality, the usefulness

00:50:42 of recombinant DNA for the analysis and manipulation of genes, and

00:50:46 particularly its importance for biotechnology, depends on both

00:50:50 the ability to join DNA fragments and the ability to propagate

00:50:54 and clone DNA in a foreign host. The invention

00:50:58 of DNA cloning was made possible

00:51:02 by two lines of basic research. One concerned genetic and

00:51:06 biochemical studies of bacterial plasmids, circles of DNA

00:51:10 that have the remarkable ability to reproduce themselves separately from

00:51:14 the chromosomes of host bacteria that harbor them. The other

00:51:18 focused on biochemical manipulations of DNA.

00:51:22 In 1968, when I joined the Stanford faculty,

00:51:26 I began to investigate the genetics and biochemistry of a mysterious

00:51:30 group of plasmids that made disease-causing bacteria resistant to the

00:51:34 effects of drugs and chemicals that ordinarily inhibit their growth.

00:51:38 Even then, antibiotic resistance was an important clinical problem, and

00:51:42 genes carried by plasmids were shown to be responsible for this resistance.

00:51:46 While plasmids had been studied for more than 15 years, little was

00:51:50 known about how they had evolved or were

00:51:54 propagated. It was Joshua Lederberg, who in

00:51:58 1952, in a Physiological Reviews article, first proposed the name

00:52:02 plasmid as a generic term for genetic elements separate from

00:52:06 chromosomes. Work reported by Donald Helinsky in

00:52:10 1967 indicated that at least some plasmids were DNA

00:52:14 circles, and studies from my laboratory and others quickly showed

00:52:18 that antibiotic resistance plasmids, such as the ones shown here,

00:52:22 were also circular. Biochemical and genetic

00:52:26 analyses revealed that such plasmids consist of two distinct components.

00:52:30 One is the RTF unit, which enables the plasmid to propagate

00:52:34 itself independently of the chromosome. The other component carries

00:52:38 genes that encode antibiotic resistance traits.

00:52:42 The field of molecular biology had developed in the 1950s and

00:52:46 1960s as an amalgam of the disciplines of genetics,

00:52:50 biochemistry, and microbiology. Bacterial viruses had

00:52:54 been the principal focus of molecular biology, largely because the

00:52:58 cloning of viruses occurs during the process of normal viral infection,

00:53:02 producing millions of genetically identical copies of a virus

00:53:06 that infects a single cell. These cloned viral

00:53:10 particles could then be studied biochemically and genetically.

00:53:14 To apply similar approaches to the study of plasmids, it would be necessary

00:53:18 to develop methods for introducing plasmid DNA into bacteria

00:53:22 and isolating clones of bacteria that inherit the

00:53:26 descendants of individual plasmid DNA molecules.

00:53:30 Mandel and Higa, two scientists working at the University of Hawaii,

00:53:34 reported in 1970 the treatment of E. coli cells

00:53:38 with a simple chemical, calcium chloride, opens up pores in the

00:53:42 envelope that surrounds these bacteria, allowing them to take up DNA

00:53:46 and to manufacture infectious virus. However, the

00:53:50 efforts of these scientists to introduce and propagate non-viral DNA

00:53:54 in E. coli had not been successful. In 1971,

00:53:58 Leslie Hsu, a first-year Stanford medical student working in my lab,

00:54:02 found that modification of Mandel and Higa's procedure

00:54:06 enabled bacteria to take up plasmid DNA and produce

00:54:10 offspring that contain self-replicating plasmids.

00:54:14 Genes on the plasmid made these transformed bacteria

00:54:18 resistant to antibiotics. They survived and grew when exposed

00:54:22 to the drugs, whereas bacteria lacking plasmids were killed.

00:54:26 Since all descendants of a transformed E. coli cell

00:54:30 contained plasmids identical to the one that originally had entered that cell,

00:54:34 it was now possible to biologically make replicas, clones

00:54:38 of individual molecules of plasmid DNA. This ability

00:54:42 to clone plasmid DNA provided one of the two key ingredients

00:54:46 for genetic engineering. To map and isolate

00:54:50 plasmid genes, I wished to take plasmids apart and put them back

00:54:54 together again, one segment at a time. In nature, antibiotic

00:54:58 resistance genes had been linked to the replication machinery of plasmids

00:55:02 by natural recombination mechanisms working within cells.

00:55:06 Potentially, the replication regions of plasmids might also be able

00:55:10 to propagate DNA segments that were attached to these regions biochemically.

00:55:14 But how to accomplish this linkage? An important

00:55:18 biochemical strategy for joining together DNA segments

00:55:22 depends on the ability of nucleotides in a single strand of DNA

00:55:26 to pair with complementary nucleotides in the other strand

00:55:30 to form a DNA duplex, the A's and G's pairing with T's

00:55:34 and C's. A bacterial virus named Lambda

00:55:38 uses this strategy in nature, as had been known from work by

00:55:42 Hershey and colleagues at Cold Spring Harbor. Complementary nucleotides

00:55:46 at corresponding positions in projecting single strands at the ends

00:55:50 of Lambda DNA joined together in bacteria during the viral

00:55:54 life cycle to create a DNA circle. Because Lambda

00:55:58 DNA circles made outside of cells contain nicks at

00:56:02 different locations in each strand, these circles were useful to

00:56:06 Martin Gellert and others for identification and isolation of an enzyme

00:56:10 that Arthur has already mentioned, DNA ligase, which can repair

00:56:14 DNA breaks. In the late 1960s,

00:56:18 work in the laboratory of Gobin Karana showed that

00:56:22 short segments of synthetic DNA strands can be

00:56:26 joined together in test tubes using the base pairing strategy

00:56:30 nature had evolved for Lambda plus the E. coli ligase.

00:56:34 However, the construction of complementary DNA ends

00:56:38 by the stepwise biosynthetic addition of single nucleotides

00:56:42 was both technically difficult and laborious.

00:56:46 In 1970, Karana's lab reported that the DNA

00:56:50 ligase of bacterial virus T4, unlike the ligase

00:56:54 of E. coli, has a remarkable additional capability.

00:56:58 The power to join together blunt DNA ends that lack

00:57:02 complementarity. Notwithstanding this discovery,

00:57:06 the scientific community still focused largely because of the

00:57:10 bacteriophage Lambda paradigm on complementary

00:57:14 termini as a method of DNA joining. A strategy that

00:57:18 circumvented the need, this was the paper showing blunt

00:57:22 DNA joining, a strategy that circumvented the need to add

00:57:26 complementary nucleotides one at a time was suggested

00:57:30 in 1969 in a PhD thesis proposal

00:57:34 by a Stanford graduate student, Peter Loban, working in the

00:57:38 laboratory of Professor Dale Kaiser in the Department of

00:57:42 Biochemistry. An enzyme discovered earlier by F. Bollum

00:57:46 of the Oak Ridge National Laboratory could add a stretch of A's to

00:57:50 one DNA fragment and a complementary stretch of T's to the other.

00:57:54 Quite independently, R. H. Jensen at the

00:57:58 International Minerals and Chemicals Company

00:58:02 devised the same strategy. And in mid-1971

00:58:06 in a little-noticed paper, Jensen and his colleagues

00:58:10 reported the very first linking together in test tubes of separate

00:58:14 DNA molecules that contained stretches of A's and T's added to their ends.

00:58:18 However, Jensen's efforts to use DNA ligase

00:58:22 to close the nicks in these recombined DNA molecules were

00:58:26 not successful. When the DNA was treated with alkali, which breaks

00:58:30 bonds between paired nucleotides, the linked molecules fell

00:58:34 apart. It is now known that nicks in such joined

00:58:38 pieces of DNA can be sealed when DNA is introduced into

00:58:42 bacteria. Loban and his faculty adviser

00:58:46 discovered that carrying out additional enzymatic

00:58:50 manipulations at the ends of AT-tailed fragments of DNA

00:58:54 from the bacterial virus P22 enabled fusion of these

00:58:58 fragments by what is biochemically called covalent leakage.

00:59:02 This finding was duly noted by Paul Berg

00:59:06 and his colleagues in their classic paper reporting

00:59:10 use of the AT-joining approach to link together DNA molecules

00:59:14 in two different biological sources, the E. coli bacteriophage

00:59:18 lambda and the mammalian virus SV40.

00:59:22 Unbeknownst to Berg at the time, the insertion of SV40

00:59:26 in lambda DNA interrupted a lambda gene

00:59:30 the phage requires for replication, as others later found

00:59:34 when they tried to propagate similar constructs, so that the biohazard

00:59:38 concerns that led Berg to decide not to introduce the DNA

00:59:42 fragments into bacteria were in retrospect moot.

00:59:46 Thus by late 1972, several

00:59:50 different methods were available for joining together separate

00:59:54 DNA molecules outside of living cells. This provided

00:59:58 the second ingredient for genetic engineering.

01:00:02 However, the splicing of DNA for the first

01:00:06 DNA cloning experiments did not depend on synthetic DNA

01:00:10 ends or even blunt-ended joining, nor did it use

01:00:14 the extraordinary advances with DNA polymerases or any

01:00:18 of the exonucleases that Arthur Kornberg has just described.

01:00:22 Instead, it depended on

01:00:26 restriction endonucleases, enzymes that have the remarkable

01:00:30 ability to recognize specific DNA sequences

01:00:34 sequences of nucleotides in DNA, and to cut these DNA

01:00:38 sequences in a way that produces projecting complementary

01:00:42 strands in one step. These enzymes and their

01:00:46 remarkable abilities had been discovered by Werner Arber in Switzerland and by

01:00:50 Hamilton Smith at Johns Hopkins.

01:00:54 In November 1972, Joe Hedgepeth, Howard

01:00:58 Goodman, and Herbert Boyer at the University of California reported

01:01:02 the nature of the sixth nucleotide sequence recognized by EcoR1,

01:01:07 a restriction enzyme encoded by a gene on an antibiotic resistance

01:01:11 plasmid. I'm a little bit ahead of myself.

01:01:15 Isolated from a patient at the University of California.

01:01:19 As seen here, EcoR1 cuts duplex DNA

01:01:23 asymmetrically within this sequence, generating projecting

01:01:27 single-strand ends. Simultaneously

01:01:31 published work at Stanford by Vittorio Scaramella

01:01:35 in the Department of Genetics and by Janet Mertz and Ronald Davis

01:01:39 in the Department of Biochemistry show that DNA segments could be

01:01:43 joined together using these complementary ends.

01:01:47 That same month at a scientific meeting in Hawaii

01:01:51 I reported our newfound ability to clone individual molecules

01:01:55 of plasmid DNA and bacteria. Later that day I listened

01:01:59 with excitement as Herb Boyer described his data showing the nature

01:02:03 of the DNA ends generated by EcoR1 cleavage.

01:02:07 I had been trying to restructure plasmids. It should be possible

01:02:11 I thought to take plasmids apart by cleaving them with EcoR1

01:02:15 and then use the complementary EcoR1 generated

01:02:19 ends to link other DNA fragments to plasmid

01:02:23 replication regions. That evening Herb and I discussed

01:02:27 a scientific collaboration which would attempt to attach other

01:02:31 DNA fragments to plasmid replication regions.

01:02:35 Fragments held together by the complementarity of the EcoR1

01:02:39 generated ends would be fused covalently and permanently

01:02:43 by DNA ligase and then introduced into bacteria using the

01:02:47 plasmid DNA cloning procedure. While the concept was straightforward

01:02:51 no one knew at the time whether the structurally modified

01:02:55 plasmids we wished to construct would be capable of propagation in living

01:02:59 cells. We began these experiments shortly after the Hawaii meeting

01:03:03 and by March 1973 had established

01:03:07 the feasibility of DNA cloning. Plasmids isolated at

01:03:11 Stanford were transported to Boyer's lab in San Francisco for

01:03:15 cutting by EcoR1 and analysis of the DNA fragments

01:03:19 and then transported back to Stanford where joined fragments were

01:03:23 introduced into E. coli by transformation. The newly constructed

01:03:27 plasmids were isolated and then analyzed by gel electrophoresis

01:03:31 at the University of California and by centrifugation at

01:03:35 Stanford. Annie Chang, a research technician in my laboratory

01:03:39 did many of the plasmid DNA isolations and bacterial transformations.

01:03:43 Since Annie lived in San Francisco she also

01:03:47 carried our precious DNA samples between the two labs almost daily.

01:03:51 Bob Helling who was on sabbatical leave in Boyer's lab

01:03:55 did many of the DNA analyses.

01:03:59 The strategy Boyer and I had devised worked better

01:04:03 than anyone could have expected and the months

01:04:07 in early 1973 were a period of almost unbelievable excitement

01:04:11 for all of us. In the very first DNA cloning

01:04:15 experiments we constructed self-propagating plasmids containing

01:04:19 only a few of the multiple EcoR1 generated fragments of a large

01:04:23 antibiotic resistance plasmid R65. These plasmids

01:04:27 had in common a DNA fragment that contained the plasmids replication

01:04:31 machinery. This fragment had become linked to various other

01:04:35 DNA fragments that carry antibiotic resistance genes but lacked the

01:04:39 capacity for replication. While this experiment immediately established

01:04:43 the feasibility of our DNA cloning strategy, to make DNA

01:04:47 cloning practical we needed a true vector or carrier molecule

01:04:51 to clone DNA fragments that lack selectable genes.

01:04:55 Among my plasmids at Stanford was a DNA circle, plasmid

01:04:59 PSC101 which carries a resistance gene for the

01:05:03 antibiotic tetracycline. We found that PSC101

01:05:07 is cut at only a single site by the EcoR1 endonuclease.

01:05:11 Because cleavage at this site did not interrupt

01:05:15 either the replication origin of the plasmid or the tetracycline

01:05:19 resistance gene it carried, PSC101 could be used as

01:05:23 a DNA cloning vector. As has since been done many

01:05:27 hundreds of thousands, if not millions of times, the plasmid

01:05:31 DNA circle was opened by cutting it with the restriction

01:05:35 enzyme. When the linearized PSC101 DNA vector

01:05:39 was mixed with another DNA that had been cleaved by the same enzyme

01:05:43 EcoR1, the complementary ends held together

01:05:47 the EcoR1 generated fragments. Ligation

01:05:51 closed the mix still present in the DNA circle, which was then

01:05:55 introduced into calcium chloride treated bacteria.

01:05:59 Spreading the bacterial population on culture media containing tetracycline

01:06:03 resulted in growth only of bacterial clones that contained

01:06:07 recombinant DNA molecules. In May 1973

01:06:11 a manuscript describing these results was prepared for submission

01:06:15 to the proceedings of the National Academy of Sciences. This paper, which was

01:06:19 published in November 1973, forms the basis for the Stanford

01:06:23 University of California patent that underlies much of modern

01:06:27 biotechnology. Were the practical significance of this basic

01:06:31 research and its potential applications in biotechnology apparent to us?

01:06:35 You bet they were. However, the demonstration

01:06:39 that DNA fragments from E. coli plasmids could be cloned in the same

01:06:43 bacterial host by inserting them into plasmid vectors

01:06:47 didn't necessarily mean that DNA from foreign species could also

01:06:51 be propagated in E. coli. It had long been believed that

01:06:55 natural barriers would prevent gene transfer between all but the

01:06:59 most closely related organisms, and scientific colleagues offered

01:07:03 cogent reasons why the transplantation of DNA

01:07:07 to unrelated organisms would not be possible. While our initial

01:07:11 collaborative studies with Boyer and Helling were impressed, Chang and I found that

01:07:15 DNA cloning using plasmids allowed so-called species

01:07:19 barriers to be breached. DNA from a Staphylococcal plasmid

01:07:23 could be propagated in E. coli by linking it to an E. coli plasmid vector.

01:07:27 In our 1974, April 1974

01:07:31 report of these results, we wrote,

01:07:35 the replication and expression of genes in E. coli that have been derived from a totally

01:07:39 unrelated species now suggests that interspecies genetic

01:07:43 recombination may be generally attainable. Thus it may be

01:07:47 practical to introduce into E. coli genes specifying

01:07:51 metabolic or synthetic functions such as photosynthesis or antibiotic

01:07:55 production indigenous to other biological classes. These

01:07:59 results support the view that antibiotic resistance replicons such as

01:08:03 the PSC-101 plasmid may be of great potential usefulness

01:08:07 for the introduction of DNA derived from eukaryotic organisms into

01:08:11 E. coli, thus enabling the application of bacterial genetic

01:08:15 and biochemical methods to the study of eukaryotic genes.

01:08:19 Shortly afterward, additional collaborative experiments between

01:08:23 Boyer's lab and mine with the participation of John Morrow at

01:08:27 Stanford and Howard Goodman at UCSF showed that eukaryotic

01:08:31 DNA could also be propagated in E. coli

01:08:35 genes transcribed there. Later, Boyer and his collaborators

01:08:39 succeeded in expressing a mammalian protein, somatostatin,

01:08:43 in bacteria and found that this protein showed normal

01:08:47 immunological reactivity. In still later experiments done collaboratively

01:08:51 with Robert Schimke at Stanford, Chang and I constructed the

01:08:55 first bacteria that synthesized the functional mammalian protein,

01:08:59 the mouse enzyme dihydrofolate reductase, thus demonstrating

01:09:03 that bacteria could produce biologically active animal cell

01:09:07 proteins and helping further to set the scene for the emergence of

01:09:11 biotechnology. This emergence was quick to come with a subsequent

01:09:15 construction of plasmids encoding insulin by scientists at

01:09:19 Genentech, by Rutter and Goodman and their associates, and by Walter Gilbert.

01:09:23 As we've seen this morning, science isn't done in a vacuum.

01:09:27 In common with most inventions, the invention

01:09:31 of DNA cloning was dependent on the fruits of years of

01:09:35 effort in many different laboratories. As with most

01:09:39 scientific discoveries, one can say with some certainty that

01:09:43 if Boyer and I had not collaborated to invent DNA cloning in early

01:09:47 1973, the cloning of DNA would later have been achieved

01:09:51 by others, probably approaching this objective from a different

01:09:55 perspective. Such is, and such should be, the nature

01:09:59 of science. Thank you.

01:10:11 Thank you very much, Stanley Cohen, for a fine

01:10:15 recapitulation of those detailed steps

01:10:19 which took you from one place to the critical

01:10:23 point where you left our discussion. Your indication

01:10:27 through that discussion of why it is you feel so confident

01:10:31 about there being a history which can be written reminds me of a story

01:10:35 of the time Hans Bethe walked in on

01:10:39 Leo Szilard, and there was Leo writing details, and

01:10:43 Hans looked at it and said, Leo, what are you writing? He said, I'm writing the history

01:10:47 of a series of experiments in particle physics. Oh, you're going to publish something.

01:10:51 Oh no, said Leo Szilard, I'm not going to publish it. Hans Bethe was

01:10:55 thoroughly confused and said, well, why are you writing it? I'm writing it for God.

01:10:59 And Hans Bethe, thoroughly confused, said, but surely God knows the history.

01:11:03 Oh yes, said Leo Szilard, but I want him to know my version of it.

01:11:11 Our next speaker inverts the order. Just to show

01:11:15 anyone in the room that a printed document is not necessarily an accurate

01:11:19 one, we're going to invert the order of Maxine Singer and Paul Berg.

01:11:23 But in calling Paul Berg to the podium, I almost have the

01:11:27 feeling of a rump meeting of the Stanford faculty about to take place.

01:11:31 But it also reminds us how important place is.

01:11:35 Stanford was clearly, and San Francisco in general, clearly an

01:11:39 extremely active place in the history of molecular

01:11:43 biology and the emerging biotechnology.

01:11:47 Paul Berg, for his work, was awarded a Nobel Prize.

01:11:51 The sophisticated kind of work that he and others were engaged in,

01:11:55 the kind of work recounted in such fine detail by Stanley Cohen,

01:11:59 indicates that this kind of work

01:12:03 can make a difference. And it's the implication of that difference

01:12:07 that Paul Berg and Maxine Singer are going to examine

01:12:11 as they turn to the question of policy as it

01:12:15 emerges from scientific advance and scientific change.

01:12:19 Paul Berg.

01:12:33 I'm reminded of Charles' opening remarks

01:12:37 when he quoted a scientist who said he'd rather be talking about the science

01:12:41 than the policy. And after listening to Stanley, I think I would like to have my chance

01:12:46 to talk about the science as well. But I'm here to address

01:12:50 the introduction of the public policy debate that ensued

01:12:54 some of the discoveries that Stanley described.

01:12:58 Now, in his classic essay on the origin of scientific revolutions,

01:13:02 Thomas Kuhn characterized normal science,

01:13:06 that is, what he referred to as the prevailing paradigm.

01:13:10 The prevailing paradigm, he viewed, is the commonly

01:13:14 represented body of facts, theories, practices, and standards

01:13:18 that are the hallmarks of a particular field of scientific inquiry.

01:13:22 Inevitably, he argued, the prevailing paradigm

01:13:26 accumulates paradoxes, contradictions, conflicts,

01:13:30 and limited means to solve them.

01:13:34 Revolutions, he surmised, are initiated by challenges to the existing

01:13:38 paradigm, either through novel insights to provide new perspectives

01:13:42 on existing

01:13:46 inconsistencies, or by the invention

01:13:50 of new tools that make it possible to extend the boundaries of knowledge

01:13:54 beyond what was previously possible.

01:13:58 By their nature, such paradigm shifts challenge long-held

01:14:02 views and practices, and therefore engender

01:14:06 widespread skepticism, resistance, occasionally

01:14:10 fear, and counter-revolutionary efforts.

01:14:14 Now, Kuhn's principal thesis is that successive

01:14:18 transitions from one paradigm to another via revolution

01:14:22 and the debates it engenders is the usual developmental

01:14:26 pattern of a progressive science. Bernard Davis

01:14:30 begins the preface of his edited volume on the genetic revolution as follows.

01:14:34 In a world surfeited with hyperbole,

01:14:38 the word revolution deservedly evokes skepticism.

01:14:42 But if it is ever useful, if it is ever

01:14:46 a useful term to characterize a fundamental change in our

01:14:50 outlook or our powers, it surely applies

01:14:54 to molecular genetics as much as to the earlier

01:14:58 agricultural, industrial, Copernican, and Darwinian revolutions.

01:15:02 I think there's no common agreement as to when

01:15:06 and how the molecular genetic revolution began.

01:15:10 Some mark its beginnings with Avery, McLeod, and McCarthy's

01:15:14 demonstration that genes are made of DNA,

01:15:18 while others believe the defining moment was Watson and Crick's

01:15:22 solution of the DNA structure. Now, whichever of these

01:15:26 or any other ones that you prefer to enlist,

01:15:30 the emergence of the recombinant DNA technology is surely a worthy

01:15:34 candidate for inclusion in that pantheon. For molecular

01:15:38 genetics, often referred to as genetic engineering,

01:15:42 now dominates research in biology. It has altered both the way

01:15:46 questions are formulated and the way solutions are sought.

01:15:50 The isolation of genes from any organism on our planet,

01:15:54 alive or dead, is now routine.

01:15:58 Furthermore, the construction of new variants of genes, chromosomes,

01:16:02 and viruses is standard practice in research laboratories,

01:16:06 as is the introduction of genes into microbes, plants,

01:16:10 and experimental animals. Equally profound is

01:16:14 the influence it has had on many related fields.

01:16:18 For even a brief look at the journals in such diverse fields as chemistry,

01:16:22 evolutionary biology, paleontology, anthropology,

01:16:26 psychology, medicine, plant science, and surprisingly enough,

01:16:30 forensics, information theory, and computer science

01:16:34 shows the pervasive influence of this new paradigm.

01:16:38 Now, interestingly, the flowering of the molecular genetic paradigm

01:16:42 occurred in the midst of a particularly raucous controversy

01:16:46 on the issue of whether this line of investigation should proceed

01:16:50 unfettered or whether it would be tightly regulated by

01:16:54 federal and state oversight. A notable feature of the debate

01:16:58 was the central role played by scientists in framing the issues

01:17:02 and in providing the leadership that ultimately led to its resolution.

01:17:06 Several critical events paved the way for the

01:17:10 scientists and public's involvement in the recombinant DNA controversy.

01:17:14 The discovery of the molecular nature of genes

01:17:18 and the growing capability for their manipulation in bacteria

01:17:22 and viruses engendered concerns about the ultimate application

01:17:26 of genetic modifications of humans. Edward Tatum

01:17:30 in his 1958 Nobel lecture speculated

01:17:34 that our increasing knowledge in genetics, and I quote,

01:17:38 may permit the improvement of all living organisms by processes

01:17:42 which we might call biological engineering, close quote.

01:17:46 Now, in the late 1960s, Joshua Lederberg

01:17:50 and James Daniele foresaw how molecular biology

01:17:54 could ultimately provide new therapies for genetic disease

01:17:58 and new means to improve crop plants. But they also

01:18:02 warned of the emergence of powerful tools for

01:18:06 eugenicists and for the development of biological weapons.

01:18:10 Indeed, the U.S. Senate held hearings, which were referred to earlier,

01:18:14 in 1968 to consider how to deal with these

01:18:18 predictions and warnings. But the issues subsequently

01:18:22 faded into obscurity. Many of the same concerns, however,

01:18:26 came to life with the emerging technology of molecular cloning

01:18:30 of DNA because the new and more sophisticated means

01:18:34 for manipulating genes made the earlier warnings seem less

01:18:38 theoretical and more immediate. The first

01:18:42 warnings that certain lines of biological research could conceivably

01:18:46 endanger public health were the rapidly expanding investigations

01:18:50 with viruses capable of producing tumors in animals.

01:18:54 The concern was that the escape of such viruses from

01:18:58 the laboratory environment might be deleterious to research workers,

01:19:02 their neighbors, and possibly to the local communities

01:19:06 and the environment. A meeting was held at the Asilomar

01:19:10 Conference Center in Pacific Grove, California in January of

01:19:14 1973, what I call Asilomar 1.

01:19:18 It brought together scientists working with tumor viruses and experts in

01:19:22 epidemiology, public health, and laboratory safety

01:19:26 to review this potential threat. The conference

01:19:30 recommended first that increased physical containment be required

01:19:34 in order to reduce the likelihood that infectious agents

01:19:38 could escape from the laboratory, and second that we institute

01:19:42 more intensive surveillance of the workers for signs of illness

01:19:46 due to infections. But the introduction of vastly

01:19:50 more powerful and potentially pervasive applications of the recombinant DNA

01:19:54 technology reignited the concerns of the earlier

01:19:58 meeting and brought them to public attention in interesting ways.

01:20:02 After hearing Herb Boyer present an especially exciting

01:20:06 result of an experiment uniting two separate DNA molecules

01:20:10 carrying different antibiotic resistance genes and propagating it in

01:20:14 a bacterium, the participants in the 1973

01:20:18 Gordon Conference on Nucleic Acids were impressed.

01:20:22 Nevertheless, they acknowledged that while this capability had unusually promising

01:20:26 potential for advancing knowledge of fundamental biological processes,

01:20:30 they might also prove, and I quote,

01:20:34 hazardous to laboratory workers and the public.

01:20:38 Close quote. Now that concern was expressed in a letter

01:20:42 published in Science Magazine by the conference's chairpersons,

01:20:46 Maxine Singer and Dieter Saul, and were relayed to the president

01:20:50 of the National Academy of Sciences for his consideration.

01:20:54 The academy responded, as most academies typically

01:20:58 do, by forming a committee, this one chaired and

01:21:02 selected by me, consisting of scientists who either were

01:21:06 or were likely to be actively engaged in recombinant DNA

01:21:10 and related work. It wasn't a surprise that several of the

01:21:14 participants of that meeting were those who had engaged the issue of safety

01:21:18 at the earlier meeting on tumor viruses.

01:21:22 Now the committee acknowledged that the recombinant DNA breakthrough

01:21:26 promised extraordinary opportunities in genetics and the applied

01:21:30 sciences in medicine, industry, and agriculture.

01:21:34 They also concluded that many experiments were not plausibly

01:21:38 hazardous and therefore should continue. There were

01:21:42 other experiments, however, whose risks were more problematic

01:21:46 and should be deferred. To deal with the uncertainties

01:21:50 posed by these experiments, the committee offered two significant

01:21:54 recommendations that became, to their surprise,

01:21:58 front page news. First, the committee recommended

01:22:02 a worldwide moratorium on certain types of recombinant DNA

01:22:06 experiments, and second, that an international conference

01:22:10 of experts be convened to consider the safety issues

01:22:14 associated with this line of experimentation. Implicit in the

01:22:18 conference's agenda was to determine if the perceived risks

01:22:22 were real or imaginary, and if the

01:22:26 former, to recommend ways to minimize or eliminate the risks.

01:22:30 These recommendations were relayed to the academy's president

01:22:34 and published concurrently in Science, Nature, and

01:22:38 the Proceedings of the National Academy of Sciences. Although

01:22:42 some saw the moratorium as an infringement of their freedom of inquiry,

01:22:46 it was, as far as anyone knows, universally

01:22:50 observed. Scientists from throughout the world,

01:22:54 together with lawyers and ethicists, members of the press, and the government

01:22:58 met at the same Asilomar Conference Center in early

01:23:02 February of 1975 to explore the issues that had

01:23:06 been raised. Although there were few data on which to base

01:23:10 a scientifically defensible judgment, the participants

01:23:14 concluded, not without outspoken opposition from some of its

01:23:18 more notable members, that recombinant DNA experimentation

01:23:22 should proceed, but under strict guidelines.

01:23:26 And such guidelines were subsequently promulgated by the National Institutes of Health

01:23:30 and comparable bodies in other countries, a period about

01:23:34 which Dr. Singer will speak shortly. Now, before

01:23:38 yielding the podium to Dr. Singer, I want to touch on an often voiced

01:23:42 criticism of the early recombinant DNA discussions.

01:23:46 This concerns the failure of the various committees and the

01:23:50 Asilomar conferees to consider the ethical and legal

01:23:54 implications of genetic engineering of plants, animals,

01:23:58 and humans. This choice of agenda

01:24:02 was due neither to oversight, nor to the unawareness of the

01:24:06 issues. It was deliberate, partly because of a lack

01:24:10 of time at Asilomar, and partly because it was premature

01:24:14 to consider applications that were so speculative and certainly

01:24:18 not imminent. In 1975, the

01:24:22 principal and more urgent concern for those that were gathered at Asilomar

01:24:27 were the possible effects of recombinant DNA on public health

01:24:31 and safety. Now, in retrospect, very few

01:24:35 of those attending the Asilomar conference foresaw the

01:24:39 pervasive, complex, robust, and rich ramifications

01:24:43 of the recombinant DNA technology. I don't think

01:24:47 too many of us could have predicted the pace at which our fundamental

01:24:51 understanding of biology has deepened and the extent to which

01:24:55 our deeper understanding is impacting on our society's values.

01:24:59 Now, to give you a bit of a flavor of

01:25:03 the mood at the time, I want to show

01:25:07 just a few slides which capture

01:25:11 let's say the public and the media

01:25:15 actions with respect to the debate. So, the first slide

01:25:19 as you will see is a cover of the New Scientist magazine

01:25:23 with hands remodeling the double helix

01:25:27 with the warning underneath of who should control

01:25:31 the genetic engineers. A second

01:25:35 magazine which had as its cover

01:25:39 this ugly-looking, viperous beast

01:25:43 emerging from the double helix of DNA with a number of white

01:25:47 frock scientists at the bottom obviously rebuilding or

01:25:51 rebuilding new DNA molecules. And you can see the landscape

01:25:55 is dotted with double helices.

01:25:59 Time magazine kicked in with its view which is

01:26:03 this face holding up a tube swirling

01:26:07 a murky-looking solution

01:26:11 presumably DNA and again the DNA

01:26:15 furor tinkering with life.

01:26:19 Three books that were published about the time of the public

01:26:23 policy debate. You'll notice they carry the very

01:26:27 alarming titles, Playing God, Biohazard

01:26:31 or The Ultimate Experiment.

01:26:35 The authors June Goodfield of Playing God and Michael Rogers

01:26:39 who authored the book Biohazard and Nicholas Wade

01:26:43 on The Ultimate Experiment. These are two additional ones

01:26:47 in which splicing life and the manipulation of life

01:26:51 fed the concern. But ultimately

01:26:55 we survived that stage and as you can see here we have

01:26:59 two businessmen toasting to recombinant DNA.

01:27:03 And then of course the New York Times

01:27:07 had to kick in with, does something like this belong in your pension portfolio?

01:27:11 And then now

01:27:15 as you will see the public is now well versed in genetic terminology

01:27:19 and so here's a recent Mercedes-Benz advertisement

01:27:23 showing four of their new models and it says genetically speaking

01:27:27 they're identical. And then the last one which I want to show

01:27:31 is the most recent one which I clipped is they come with

01:27:35 ABS, ASR, ESP and SRS and those of you who follow

01:27:39 otolingo will recognize those terms

01:27:43 What really counts is DNA and what you can't read

01:27:47 but I'll read for you says the genetic material that makes the S-class

01:27:51 of Mercedes-Benz evolved over

01:27:55 111 years of continuing luxury before and so on and so forth.

01:27:59 So I don't want to do their private

01:28:03 advertising. In any case you can see that

01:28:07 how science has infiltrated now the business community even those

01:28:11 unrelated to biotechnology. But I'd like to turn the podium

01:28:15 over to Dr. Singer now who will follow along with describing

01:28:19 what followed from the Asilomar conference. Thank you.

01:28:23 Thank you very much

01:28:27 Paul Bird for taking us right into the middle of the policy

01:28:31 discussions which you yourself were in the middle of as they began as

01:28:35 they continued. I first met Maxine Singer at the Cambridge City

01:28:39 Council in 1976 when she came up from the NIH to take

01:28:43 part in a hearing on recombinant DNA experimentation

01:28:47 at Harvard and there she was in this ornate

01:28:51 council room filled with people, the mayor Al Valucci, worried

01:28:55 about the creepy crawlies in the laboratory. He's a man who every year used to

01:28:59 introduce a motion to pave over Harvard Yard and make it a parking lot

01:29:03 but a bit of humor

01:29:07 But Maxine Singer, as Paul Bird indicated, had been involved

01:29:11 from the very beginning in the discussion of the nature of the problems

01:29:15 in recombinant DNA work and the role of scientists in the nature

01:29:19 of the responsibility that they should be taking. She received the

01:29:23 National Medal of Science for her work in recombinant

01:29:27 DNA work in other areas. She's currently the president of the

01:29:31 Carnegie Institution but perhaps from the point of view of some of us in the room what

01:29:35 most marks her current work and Paul Bird's current work is that they're becoming

01:29:39 historians. They're in the midst of a biography of George Beadle

01:29:43 Maxine Singer.

01:29:47 Actually, the Cambridge hearing presented me with

01:29:51 one very difficult ethical problem

01:29:55 because Mayor Valucci was being very cautious about

01:29:59 who was testifying and who represented what position

01:30:03 and you were only supposed to be from MIT or from Harvard

01:30:07 or from the city of Cambridge and I was none and he kept pressing

01:30:11 me to say, well, are you a Harvard person? And it was

01:30:15 a big problem for me because in fact, of course, I am a Yale person.

01:30:19 That was just one of the sidelines. But as

01:30:23 many people have noted, the Asilomar Conference really marked the end

01:30:27 of the beginning of the recombinant DNA story. Up until

01:30:31 that time, science had been the core topic

01:30:35 and scientists the central participants. But that began

01:30:39 to change within 24 hours of the end of the conference

01:30:43 and by the time a few years had passed, the discussions were

01:30:47 a multi-ring phenomenon, sometimes even a multi-ring

01:30:51 circus. The first meeting of the recombinant DNA

01:30:55 advisory committee to the director of the NIH, what

01:30:59 came to be called the RAC, was held the day after Asilomar

01:31:03 ended. The RAC adopted the Asilomar recommendations

01:31:07 as interim guidelines for investigators who were operating

01:31:11 with NIH grants, although they had not yet been finalized

01:31:15 or even reviewed by the National Academy of Sciences.

01:31:19 NIH became then the major focus of

01:31:23 activity in the United States until June 23rd

01:31:27 1976, which was the day that the NIH

01:31:31 published the guidelines for research involving recombinant DNA

01:31:35 molecules. The development of those guidelines was

01:31:39 accompanied by constructive, if complex, and sometimes

01:31:43 contentious debates. The guidelines were, however,

01:31:47 widely accepted by the scientific community,

01:31:51 by the Department of Health, Education, and Welfare, and by the

01:31:55 public. And this success was really to the credit of the two

01:31:59 very wise and distinguished biomedical scientists who were then at

01:32:03 the helm of the NIH. DeWitt Stetton was

01:32:07 associate director of the NIH, and his job was

01:32:11 to chair the RAC and to see to it that the scientific

01:32:15 community developed workable guidelines based on the Asilomar

01:32:19 report. His challenge was to assure consideration

01:32:23 of a spectrum of opinions and to channel them into closure.

01:32:27 Don Fredrickson was the new director of the

01:32:31 NIH. He was to spend a very large percent of his six

01:32:35 year tenure in that position as a go-between, peacemaker

01:32:39 and dealmaker between scientists and the Department of

01:32:43 Health, Education, and Welfare, other federal departments and

01:32:47 agencies who were concerned with the research, the Congress,

01:32:51 and the public. He was committed, abetted by his

01:32:55 very close advisor, Joseph Perpich, to continue and even

01:32:59 expand the completely open public process that had been

01:33:03 started by scientists. However, while the scientists had sort of

01:33:07 bungled their way into this mode, Fredrickson's position

01:33:11 was deliberate and well-conceived. He believed strongly

01:33:15 in the great promise of the new methods, and he understood

01:33:19 that without scientifically defensible yet flexible guidelines

01:33:23 the promise of the research could not be realized. He knew

01:33:27 from the start that such a goal was attainable only through openness.

01:33:31 Statton's group met next in May

01:33:35 of 1975. The upshot of those discussions

01:33:39 was to ask David Hogness of Stanford University to draft a

01:33:43 set of guidelines for discussion based on the Asilomar recommendations.

01:33:47 The Hogness draft was the main agenda item

01:33:51 for a September meeting of the RAC at Woods Hole, where the

01:33:55 draft was generally viewed as too stringent.

01:33:59 When the Woods Hole modifications were circulated, they were judged to be

01:34:03 too lenient. Statton then established a

01:34:07 subcommittee to redo the Woods Hole version. The chair of that

01:34:11 committee was Elizabeth Cutter of Evergreen State College

01:34:15 in Washington, and in the Cutter version, which became

01:34:19 available in the fall, the pendulum swung back the other way.

01:34:23 This seesaw history of guideline drafting, like the

01:34:27 Asilomar discussions themselves, reflected the basic

01:34:31 difficulties, the biases of different committee members,

01:34:35 and the increasing numbers of scientists who were expressing opinions.

01:34:39 The most fundamental problem was, of course, that

01:34:43 nobody could make any reasonable estimate of risks if

01:34:47 indeed they existed at all. There were no data, there were no relevant

01:34:51 experiments. There was only the informed intelligence

01:34:55 of trained people and speculation.

01:34:59 Unfortunately, informed intelligences differed wildly

01:35:03 concerning the probabilities of hazard for any particular

01:35:07 experiment, and the numbers went from zero to some larger number.

01:35:11 And also disagreement about the severity of the consequences

01:35:15 of any imagined hazard. Additionally,

01:35:19 many people were distrustful of the physical containment procedures

01:35:23 to provide adequate protection, especially in the hands

01:35:27 of molecular biologists rather than trained microbiologists.

01:35:31 Another problem was the extent to which people had

01:35:35 confidence in the not yet proven concept of biological

01:35:39 containment. It was by then well known that E. coli

01:35:43 K-12 was proving difficult to disarm in spite of Roy Curtis'

01:35:47 extraordinary efforts. One thing that simplified

01:35:51 the deliberations somewhat was the agreement that the

01:35:55 immediate relevant issue would continue to be safety for lab

01:35:59 workers, the general public, and the environment, and not the thorny

01:36:03 ethical questions that would later require attention.

01:36:08 Added to all of this was a sense that time mattered. I wrote

01:36:12 to Elizabeth Cutter in mid-October of

01:36:16 1975, urging haste.

01:36:20 It is already very late. Many investigators have no doubt

01:36:24 already lost patience with the delays, and each

01:36:28 investigator who is now working, or begins to work, with his own

01:36:32 interpretation of the Asilomar Guidelines will have a snowball effect

01:36:36 on others who are anxious to start.

01:36:40 Stetton was also worried about the timing because

01:36:44 he feared congressional actions might overtake the guideline process.

01:36:48 And in early November he wrote to one RAC member, there was

01:36:52 general agreement that we would be far better off if no laws were

01:36:56 written in this area. But Stetton was dedicated to fairness

01:37:00 and he conceived the devilish process for resolution of the situation.

01:37:04 He circulated to the RAC members and a few others

01:37:08 including several members of the Asilomar Organizing Committee who

01:37:12 were invited to the December 1975 meeting of the RAC

01:37:16 at La Jolla. He circulated what he termed a variorum version.

01:37:20 Three columns on each page gave, in corresponding rows,

01:37:24 the recommendations of the three versions. Hoganess,

01:37:28 Woods Hole, and Cutter. And at La Jolla this was debated

01:37:32 line by line. Those were a difficult few days

01:37:36 relieved only by some occasional hilarity engendered

01:37:40 by exhaustion and the firming of friendships that were

01:37:44 to last for many years. The red revisions

01:37:48 marked on my file copy of the variorum edition reveal

01:37:52 that virtually every decision was in favor of stringency.

01:37:56 Stetton was satisfied and in late December he forwarded

01:38:00 the La Jolla recommendations to Fredrickson who promptly asked

01:38:04 his Director's Advisory Committee to consider the document in early

01:38:08 February. Mike Rogers, the person who wrote that book

01:38:12 Biohazards that Paul showed you a few minutes ago,

01:38:16 who was a writer then for Rolling Stones magazine and had

01:38:20 been at Asilomar, identifies this Director's Advisory Committee

01:38:24 meeting as the real starting point for public engagement in the issue.

01:38:28 Fredrickson had invited everyone in and

01:38:32 solicited opinions from the public. And the convenient Bethesda

01:38:36 venue brought out the outspoken East Coast activists,

01:38:40 scientists and non-scientists alike, and plenty of journalists.

01:38:44 The Advisory Committee members themselves were an interesting

01:38:48 mix. A very distinguished jurist, academic administrators,

01:38:52 a student, a consumer representative, for example. And as

01:38:56 Rogers reports, several aspects of the tumultuous debate that

01:39:00 was to rage for the next several years became apparent at that

01:39:04 meeting. One was the difficulty of explaining

01:39:08 recombinant DNA to anyone outside of the field.

01:39:12 Paul Berg was the person who started out to try and do this.

01:39:16 And he began the meeting by describing the science. He tried to

01:39:20 clarify and enliven his presentation with brightly colored big

01:39:24 plastic puppet beads representing the DNA nucleotides.

01:39:28 We were all to carry such beads around the country and the halls of

01:39:32 Congress over the next couple of years. But as Rogers reports,

01:39:36 midway through Berg's presentation, some of the eyes of

01:39:40 the committee had already taken on a glaze. And most

01:39:44 of the news reporters were either scribbling desperately or else

01:39:48 writing nothing at all. After everyone was tranquilized

01:39:52 by Berg, I had the challenge

01:39:56 of presenting in the second hour to explain the

01:40:00 proposed guidelines. And in fact, that necessitated defining, for example,

01:40:04 the difference between a prokaryote and a eukaryote, and also

01:40:08 what a number like 10 to the 9th actually

01:40:12 meant. Well, this lack of comprehension of what were difficult

01:40:16 topics, even for experts, was to plague the history

01:40:20 of the whole public debate. Over time, some of us simplified

01:40:24 our presentations more and more, finally developing

01:40:28 frustrating concerns about the possibility of informing

01:40:32 the public adequately. Sidney Brenner, the gifted

01:40:36 and amusing British biologist who was a member of the Asilomar organizing

01:40:40 committee, underscored this issue in his own way at the press conference

01:40:44 that followed Asilomar. One of the reporters was having trouble

01:40:48 grasping the notion of biological containment. The

01:40:52 reporter seemed astonished at the notion that some bacteria might actually

01:40:56 explode under inhospitable conditions.

01:41:00 And Brenner responded deadpan, well,

01:41:04 they don't generally make a loud noise.

01:41:08 There were several other elements that were raised by members

01:41:12 of the director's advisory committee and representatives of the public during that

01:41:16 meeting that were constant issues in the years to come. One

01:41:20 was the supposition that because scientists had raised questions

01:41:24 about the safety of recombinant DNA experiments, there must be a

01:41:28 real hazard. Another was skepticism about

01:41:32 science's ability generally to improve the human condition.

01:41:36 Another was a distrust of industry because it was driven by

01:41:40 the profit motive. Yet another was to avoid discussion

01:41:44 of difficult but critical technical issues by emphasizing

01:41:48 procedural matters or questions about who should be deciding

01:41:52 about the future applications of the experiments. Still

01:41:56 at the director's advisory committee and in the debates, constructive matters

01:42:00 were raised, particularly about the processes by which the guidelines

01:42:04 could be administered.

01:42:08 Shortly after that meeting, the debates that you've already heard

01:42:12 about began in various places in the country and at various levels.

01:42:16 Meanwhile, Don Fredrickson and the executive

01:42:20 recombinant DNA committee he had established within the NIH spent

01:42:24 the next months analyzing all the comments from the meeting

01:42:28 and from the many letters that poured in. I was at that time on

01:42:32 the scientific staff of the NIH and I was part of that executive

01:42:36 committee. And finally, on June 23, 1976,

01:42:40 the guidelines were published, preceded by Fredrickson's lengthy decision

01:42:44 document. The guidelines actually looked a lot like the

01:42:48 La Jolla document, except for the addition of a variety of procedural

01:42:52 matters, particularly definitions of the responsibilities

01:42:56 of various participants from principal investigators to the

01:43:00 required institutional biohazard committees to the RAC itself.

01:43:04 Among the documents that were received during

01:43:08 the comment period leading up to the guideline publication was a letter

01:43:12 from the Environmental Defense Fund stating that the EDF

01:43:16 concerned that the guidelines applied to NIH grantees only

01:43:20 was worried about what industry would do, and that therefore they

01:43:24 believed that legislation embodying the guidelines was necessary.

01:43:28 In some straight sense, this was good news

01:43:32 because it was a vote of confidence for the guidelines,

01:43:36 although I'm not sure they meant it that way. But the main point was

01:43:40 that the EDF would pursue this concern with the Congress,

01:43:44 which they did, and you've already heard that after many years and

01:43:48 many, many bills being introduced, no federal legislation

01:43:52 was ever passed. Another

01:43:56 wake-up call came in letters from, among others, the

01:44:00 University of Michigan School of Natural Resources. This letter pointed out

01:44:04 that the National Environmental Policy Act, or NEPA, as I learned

01:44:08 finally to call it, required that federal agencies go

01:44:12 through a formal process resulting in an environmental impact

01:44:16 assessment and statement before taking any major

01:44:20 actions. By mid-May, the executive committee had

01:44:24 concluded that this was a serious matter, and we were

01:44:28 obviously about to publish the guidelines and unlikely to have an

01:44:32 environmental impact statement before then. We learned that

01:44:36 most environmental impact statements were written by contractors

01:44:40 who knew all about the law's requirements and how such documents

01:44:44 should be prepared, but it was clear that we would have to spend a lot

01:44:48 of time educating them and critiquing and editing any document

01:44:52 that they might prepare. That didn't seem like a good way to spend

01:44:56 time, and preparing the document didn't seem like such a big job.

01:45:00 We would need to recast debates and conclusions that we

01:45:04 already knew well. So it was decided that NIH would prepare the document

01:45:08 on its own. Bernie Talbot, who worked in the director's

01:45:12 office and I, got the job, along with an extensive instruction

01:45:16 manual, and we spent several weekends

01:45:20 checking off the instructions and writing things and ultimately

01:45:24 thought we were finished. But we didn't understand, we were really naive,

01:45:28 that an environmental impact statement is fundamentally a legal and

01:45:32 political document, not a scientific one. Nor did we

01:45:36 understand that brevity, our document was just under 100 pages long,

01:45:40 would itself be taken as inadequacy. We failed

01:45:44 to recognize that the experts and contractors were in fact

01:45:48 not very happy to be shut out from the job, and they would

01:45:52 be among the reviewers. We didn't know that there

01:45:56 would in fact be rounds of reviews and comments to be dealt with,

01:46:00 most of them redundant to those we'd already dealt with for the

01:46:04 guidelines. And it was certainly not a help in early July

01:46:08 to read a letter to Fredrickson from Paul Berg, who was a total

01:46:12 novice in the requirements for environmental impact statements, saying

01:46:16 overall I found it spotty in quality.

01:46:20 Four drafts later, on August 31,

01:46:24 1976, Fredrickson decided it was finished and

01:46:28 published it for public comment. In July of 77,

01:46:32 almost a year later, we were still revising the document when the

01:46:36 Friends of the Earth filed a lawsuit claiming that the NIH had failed to

01:46:40 comply with NEPA by publishing the guidelines before

01:46:44 an environmental impact statement, which of course it had.

01:46:48 The effect of such a lawsuit could have been to stop all work. But several

01:46:52 years later, a federal judge decided that the statement, in fact,

01:46:56 was okay. And I'd like to interject here a personal note.

01:47:00 In the papers you received as background for this meeting, there's

01:47:04 a quote of something I said

01:47:08 at a meeting on recombinant DNA in England in 1979.

01:47:12 In talking about the Gordon Conference and its

01:47:16 aftermath, I am quoted accurately as saying, one of the worst

01:47:20 things that ever happened to me, and my life changed from that day,

01:47:24 meaning the Gordon Conference. The context in which the quote is put in

01:47:28 the papers you got somehow makes it seem

01:47:32 as though I regretted what happened at the Gordon Conference

01:47:36 with respect to the policies, and I would really like to correct

01:47:40 that. It was really more to do with the effects that all of

01:47:44 this had on my laboratory efforts and my family

01:47:49 life, which indeed I did regret.

01:47:53 One of the most influential arguments for extreme caution

01:47:57 with recombinant DNA experiments was made by Robert Sinsheimer, who was

01:48:01 then the head of the biology division at Caltech, and

01:48:05 a highly accomplished scientist. Sinsheimer was concerned

01:48:09 that the mixing of eukaryotic and prokaryotic DNA in

01:48:13 recombinant DNA experiments would breach a natural and absolute

01:48:17 barrier with unimaginable effects on biological

01:48:21 evolution. The argument was widely adopted, in part

01:48:25 because it was simpler than the difficult, detailed discussions

01:48:29 about the potential for hazard in a variety of complex experiments.

01:48:33 And it always seemed ironic to me that in a nation

01:48:37 where many people state that they do not accept the proven fact

01:48:41 of biological evolution, Sinsheimer's position should

01:48:45 have gained such widespread support, but it did.

01:48:49 Recombinant DNA experiments themselves later demonstrated that

01:48:53 exchanges of DNA among organisms have proceeded in nature,

01:48:57 most significantly in the origin of eukaryotes themselves,

01:49:01 when a bacterium took up residence in another cell

01:49:05 and evolved into mitochondria.

01:49:09 Soon after the guidelines were published, as we've already heard,

01:49:13 several localities around the country, particularly those that

01:49:17 were home to major research institutions, undertook their own

01:49:21 public discussions and considerations of local legislations.

01:49:25 The initiative of the Cambridge, Massachusetts City Council

01:49:29 was one of the earliest, and those hearings were actually held

01:49:33 the first of the hearings was held the same day the guidelines were released

01:49:37 in June of 1976. Those debates were complex,

01:49:41 they were compounded by Harvard-MIT rivalries,

01:49:45 by Old Town gown disputes, and by a

01:49:49 divided scientific community. One had to sympathize a little bit

01:49:53 at least with the somewhat cranky and unpredictable

01:49:57 Cambridge mayor, Alfred Vellucci, who was faced on one evening

01:50:01 with Nobel laureates on either side of the aisle.

01:50:05 By July of 1977, the first

01:50:09 relaxing revisions were being made in the guidelines by the RAC.

01:50:13 The science had continued to move rapidly, while administrative

01:50:17 and legal activities moved at their typical glacial speeds.

01:50:21 And this disparity actually turned out to be important.

01:50:25 Much of the criticism, and certainly those

01:50:29 objections to the delayed environmental statement, were based

01:50:33 on the fact that NIH had moved too rapidly, that it had

01:50:37 not carefully considered all the options and alternatives

01:50:41 to the guidelines. It was not obvious to the people who made

01:50:45 such comments, as it seemed to be to us, that without the guidelines

01:50:49 the research itself would have progressed much more freely.

01:50:53 If the critics were really worried about the safety of experiments,

01:50:57 they should have recognized this. And this was, I think, an

01:51:01 additional clue to the very complex agendas of some critics.

01:51:05 From 1978 through 1982,

01:51:09 substantial changes were made in the guidelines in recognition

01:51:13 of accumulating evidence that the likelihood of generating

01:51:17 hazardous organisms was, in fact, vanishingly small

01:51:21 for almost all experiments being carried out or considered.

01:51:25 The containment requirements and oversight requirements were diminished

01:51:29 in a series of steps.

01:51:33 Originally prohibited experiments became possible under controlled conditions.

01:51:37 Some claimed that the modifications were based

01:51:41 on political concerns, not on scientific information.

01:51:45 But in fact, there was plenty of relevant science that had been

01:51:49 accumulated to support those decisions.

01:51:53 All of them were made by the NIH

01:51:57 upon recommendation from the RAC, which by the late 1970s

01:52:01 had very substantial representation

01:52:05 from non-scientists. And almost simultaneously

01:52:09 similar changes were made in Great Britain, which had adopted

01:52:13 controls on the work beginning around the time of Asilomar.

01:52:17 Surely some of you have noticed that throughout this historical

01:52:21 review I've not spoken at all about what was driving

01:52:25 those of us who spent so much time and effort on the development

01:52:29 and modification of the guidelines. The basic motivation was

01:52:33 in fact to allow the research to progress with minimal chance

01:52:37 of hazard should some of the imagined scenarios

01:52:41 turn out to be real. Why did the research

01:52:45 seem so important? Why was the simple expedient

01:52:49 of just stopping and waiting a while so unacceptable?

01:52:53 Twenty years ago, many of the involved scientists

01:52:57 answered this question with what seemed like dream-like

01:53:01 scenarios of the extraordinary insights into biology that

01:53:05 the technique could unfold. They would have gone on to talk

01:53:09 about the potential for new understandings of disease

01:53:13 and even therapies for intractable diseases. Some would have

01:53:17 mentioned the potential for agriculture and animal husbandry.

01:53:21 It all would have sounded just a little bit too good

01:53:25 to be true and too important to be true.

01:53:29 But in fact, it has turned out to be more fruitful

01:53:33 than even the most optimistic dreamers imagined.

01:53:37 There's no time now for even a hint at the breadth and depth

01:53:41 of what the new biology has achieved. Most of it

01:53:45 was unpredictable on the day the guidelines were published.

01:53:49 But I would like to mention just one example of an issue

01:53:53 that was inconceivable even as late as 1980

01:53:57 and it will be enough, and that is the AIDS epidemic.

01:54:01 Can we imagine what the course of that epidemic

01:54:05 would have been if the tools of recombinant DNA

01:54:09 had not been available at that time

01:54:13 to help us understand the viral origins of the disease,

01:54:17 the nature of the virus, ways to diagnose

01:54:21 the disease, and finally

01:54:25 the production of promising

01:54:29 and highly sophisticated drugs that give us some

01:54:33 reason for hope with this terrible situation.

01:54:37 To me, that just by itself

01:54:41 is an example of what the fruits of this work have been.

01:54:45 Thank you.

01:54:51 Thank you very much, Maxine Singer,

01:54:55 for a fine examination of the

01:54:59 interstices of making social policy

01:55:03 in an area of intensely active biological research.

01:55:07 I was reminded by some of your stories of

01:55:11 what it was like in Cambridge in those days, and one of the outcomes

01:55:15 of those funny hearings at city council was Mayor Al Vellucci

01:55:19 organizing science at the Saturday market,

01:55:23 and for a series of Saturdays, my colleagues from Harvard and MIT

01:55:27 with sleeves rolled up in the hot sun came down with slide projectors

01:55:31 and these great models of molecules

01:55:35 to demonstrate to sometimes sympathetic,

01:55:39 sometimes puzzled, but always interested large group

01:55:43 of the public. There was one other episode that I remember,

01:55:47 taking a group of my students to one of the other outcomes of those

01:55:51 hearings, and that was the establishment of the Cambridge Experimental Review Board,

01:55:55 which met for a group of citizens, that is not the university people,

01:55:59 which met week after week, 75 hours in all of hearings,

01:56:03 and at one of the meetings early on, one of my distinguished colleagues

01:56:07 literally attempted to snow this group of citizens,

01:56:11 and one active political woman from the other side of Cambridge

01:56:15 looked up and said, Professor, I don't understand what you're talking about,

01:56:19 and she said, if I don't understand you, you're not going to get your building permit.

01:56:23 He drew a deep breath and started all over again,

01:56:27 and in some of the most interesting and thoughtful

01:56:31 explanation, brought a lay group to understand the complexities

01:56:35 of the problem. In that sense, these were very possible

01:56:39 issues to deal with with a citizenry.

01:56:43 We've got a chance for a break now, people to stretch their legs,

01:56:47 walk around. In a little less than half an hour, we'll call you back.

01:56:51 Thanks a lot.