See
earlier post for preamble and reasons why I'm posting an old essay.
GENETICS LIBRARY PROJECT
THE POLITICAL ASPECTS OF GENETIC ENGINEERING
1979
THE NATURE OF GENETIC ENGINEERING — “HYBRID DNA MOLECULE”
FORMATION.
Restriction enzymes are a class of proteins produced by
organisms in order to attack and render harmless invading or foreign DNA. Each
type has a recognition site at which it attaches, and then subsequently breaks each
strand of DNA, either at a specific sequence or merely close to the recognition
site, depending on the enzyme. The recognition sequence is generally a
palindrome. The cuts do not occur straight across the DNA and generally leave
single—stranded tails, half of which are identical and half of which are the
complementary sequence. (See diagram A) Depending on the frequency of this
sequence in a given DNA molecule, the restricted fragments may be long or
short.
Once work began in earnest on Restriction Enzymes, it was
recognised that fragments restricted by one enzyme would form loose
associations by hydrogen bonding of the single—stranded tails. This gave rise
to the possibility of finding a plasmid with one restriction site, opening it
to a linear molecule by the restriction enzyme, and joining the plasmid to a
restricted piece of DNA from a different 4 source. This would form a plasmid
containing a piece of foreign DNA, a Hybrid Plasmid. Using the self—replicating
capability of the original plasmid, the piece of foreign DNA would be
propagated in a bacterial cell or ‘cloned’.
It was later discovered how to covalently link the two kinds
of DNA, making a more stable hybrid, but a problem was encountered in getting
high yields. The hybridising process was forming plasmid—plasmid hybrids,
foreign-foreign hybrids and the wanted plasmid-foreign hybrids. Eventually a
method was discovered to increase the yield by adding to the single—stranded
tail a series of identical bases using poly(dT) and tailing the other species
of DNA. with poly(dA). This meant that the different species preferentially
joined with each other, and also obviated the need for covalently joining the
hybrid molecule as the long complementary sequence gave the molecule sufficient
integrity.
THE SOURCE OF THE DNA
Both prokaryotic and histone—deprived eukaryotic DNA can be
cloned, in this manner, although eukaryotic gene regulation is different and a
gene placed into a bacterium may not be expressed unless supplied with a
prokaryotic promoter.
—2—
SELECTION AND PURIFICATION OF THE DNA
The most common method of preparing DNA for insertion is
‘Shotgunning’, involving extraction of the DNA of whole cells, which is then
restricted, prepared and inserted into the plasmid. With this method there is
no check on the content of the plasmid —
it may contain a whole gene or one restricted in the centre, or it may
merely contain a random piece of repetitive DNA.
The plasmid generally contains an antibiotic—resistance
factor so that cells taking up an hybrid plasmid can be distinguished from the
rest on growth in a medium containing the antibiotic. The remaining cells are
diluted and spread on agar. Each cell grows into a colony, and all the colonies
hopefully form a ‘library’ of the total genome of the donor cell. These can be
kept for future sequencing and analysis.
Secondly, the DNA may be partly characterized after
restriction by its molecular weight as determined by gel electrophoresis.
Thirdly, a specific gene may be identified with a
hybridization of its mRNA, after melting the DNA into single strands.
Alternatively, also in a situation where the mRNA can be purified, a system can
be set up using reverse transcriptase to make DNA complementary to the
messenger. However, this cDNA does not contain any spacers or ‘punctuation
marks’ present in the original gene, and therefore may not be expressible in a
bacterium.
Finally, if the amino—acid sequence of the desired protein
is known, using biochemical techniques developed by Khorana and co—workers, it
is possible to synthesize DNA molecules base by base. This has been successful
in producing Somatostatin, a commercially important brain protein only 14
amino-acids long. Although the initial expenditure is enormous, once the gene
is functioning it costs only as much as maintaining an ordinary culture of E.
Coli.
Although of necessity oversimplified, this short review
covers techniques generally used in the formation of hybrid plasmids. The
possibilities for this technique are endless, from cheap insulin (which is now
being produced in the lab), to a whole range of antibiotics. It will be
possible in the future to cure defective genes in Man, but it is impossible to
discuss the morals of this move here.
However with the growing recognition of the ability of DNA
molecules to ‘jump’
—3—
from site to site, to be taken up as a naked molecule and
recombined inside a cell, it became necessary to ask the question: “Is it
dangerous to transfer genes of unknown ability to the ubiquitous E. coli, whose
natural habitat is inside the human gut?”
—4—
THE RECOMBINANT DNA DEBATE
A yearly conference of molecular biologists takes place in
America, known as the Gordon Conference on Nucleic Acids. In 1973 this took
place at New Hampton, Hampshire, where advances in recombinant DNA technology
were discussed. From this discussion conferees voted to send a letter to Philip
Handler, President of the National Academy of Sciences, about the possible
consequences of the new technology. The letter stated:
“We are writing to you on behalf on a number of scientists,
to communicate a matter of deep concern...(description of the capabilities
of the science)... new kinds of hybrid plasmids or viruses, with biological
activity of unpredictable nature may eventually be created. These experiments
offer exciting and. interesting potential both for advancing knowledge of
fundamental biological processes and for alleviation of human suffering.
Certain such hybrid molecules may prove hazardous to lab workers and to the
Public. Although no hazard has yet been established, prudence suggests that the
potential hazard be seriously considered.”
The letter was printed in Science 181 1114, 1973.
The signatories to the letter were Maxine Singer and Dieter
Soll. Singer knew more than was presented at the conference. In 1972 she had
been in contact with Paul Berg, a researcher at Stanford University. Berg was
currently working with SV40, a monkey tumour virus. This virus had been
accidentally injected into millions of young Americans in the late 1950’ s in
contaminated Polio vaccinations; although no ill effects seemed to ensue, this
had caused an interest in SV40 leading to it becoming a lab favourite.
Berg was working with SV40 in order to carry animal genes
into other cells, much as a ‘phage is used to transfer bacterial genes. As
animal genes were not available at that time, Berg was using Lambdadv for
transference into animal cells. It was subsequently realised that if gene
transference could occur one way, then perhaps Lambda could transfer the
oncogenic SV40 DNA into bacterial cells. There was no evidence for or against
this possibility, and work was shut down while Berg talked about the ethics of
his work to various people, one of whom was Singer. (Biohazard pp34-38)
Although outwardly little notice seemed to be taken of the
letter, much discussion must have taken place, and on the 26th of July 1974, a
letter appeared in Science signed by 11 leading scientists of the field calling
themselves The Committee on Recombinant DNA. They included Paul Berg, David
Baltimore, Stanley Cohen, and James Watson. The letter called for “scientists
of the world (to) join with this
—5—
committee in voluntarily deferring the following types of
experiments, which were the construction of hybrid plasmids containing drug
resistance or bacterial toxin that would be used with bacteria not already
carrying these genes and in combinations not already found in nature, and
secondly the linkage of whole or restricted DNA from oncogenic or other animal
viruses to plasmids. The letter also included information on a recent success:
Goodman et al’s insertion of the Xenopus laevis DNA coding for ribosomal RNA
into a bacterial plasmid, after which RNA complementary to the original DNA had
been produced in an E. coli cell.
The letter also called to the Director of the National
Institutes of Health (NIH) to set up an advisory committee, and promised an
international meeting of scientists to work out guidelines with a view to
ending the ‘moratorium’ as the deferral came to be called. Part of the letter
was also reproduced in Nature, July 19th 1974 (vol 175) with the headline “NAS
ban on plasmid engineering.”
In Nature, July 26th, a reply from the NIH was reported. A
letter had been sent to NAS president Philip Handler by the director,
indicating that he would set up a committee to look into the possible hazards
of the research, and that he would support a meeting of scientists. Asked if
the moratorium was established, Baltimore replied that peer pressure meant that
no scientist would now undertake such experiments. This later proved to be
correct as two researchers destroyed several years work on realising it to be
outside the guidelines at that time in force. Peer pressure also involved
various Journals refusing to publish the work of these who undertook
‘forbidden’ experiments, and this may well have been a stronger factor in
discontinuation than respect for another’s opinion. In this article the first
personal opinions began to appear. Ken Murray wrote “The wisdom of using a
normal enteric bacterium as host organism in these experiments might be
questioned...(others might be used but this)...would be to forsake the wealth
of information and experience with E. coli and its viruses accumulated from
decades of research.” An article by Prof. Anderson of Colindale appears headed
by a quote “The indiscriminate use of antibiotics has exerted more pressure on
the bacterial population than could be wielded by all research workers in the
field put together.” He also believed that care in using Physical Containment
techniques would be sufficient, following the rules laid down for the handling
of dangerous pathogens. “The average microbial geneticist or molecular
biologist, (their) manipulation chills the blood of anyone accustomed to
handling pathogens.” However with the two English laboratory—started outbreaks
of Smallpox, among other things, this is no longer a popular view.
In Britain, the subject was taken very seriously. By January
1975, the Government working party set up to investigate had produced a
document, The Ashby Report on
—6—
the Experimental Manipulation of the Genetic Composition of
Micro—organisms. (Cmnd 5880 HMSO Jan 1975.) The report discussed the
capabilities of the science, and recommended that in order to encourage
research, a second working party should be set up to lay down guidelines in the
handling of recombinant DNA. In the meantime the moratorium appears not to have
been totally voluntary. There are hints in the literature that directives were
handed down to researchers asking them to refrain from the two classes of
experiments in the Berg letter.
In the United States, the promised international meeting of
scientists took place in February at Asilomar. In attendance ‘were over 150
workers in the field. Many had been briefed before the meeting to form into
groups and work out documents to present to the meeting in their own specialist
areas. These documents were read and discussed. he idea was to classify
experiments according to possible danger and work out a containment system for
each level of hazard. The first task was to explain the techniques involved to
the laymen reporters and lawyers present, and then to try to explain them to
the other groups, as the field was so new that the ‘phage group, say, had very
little in common with the eukaryotic group.
At one point James Watson rose to ask “Why, according to the
panel, is Xenopus DNA safer to work with than say, cow DNA?” A1thouh this
phylogenetic distance principle is now firmly established, no one at the time
wanted to answer Watson. The principle assumes that DNA from a source far
removed from humans is less likely to be pharmacologically active, and also
less likely to carry viral DNA sequences harmful to man than, say, simian DNA.
As discussions grew more heated, the scientists discovered the limitation of
their own fields (one talked about the possibility of getting malaria from
mosquito genes in E. coli, to the derision of others) and the difficulty of
coming to an overall agreement on relative dangers which had not been
demonstrated and had no parallels up to the present. What is the danger to the
relatively unexplored E. coli ecology of a strain carrying a random eukaryotic
DNA sequence? Would the ‘coddled’ lab strain, E. coli Kl2, survive outside the
lab in competition with wild—type? Is working with a live virus more or less
dangerous than cloned viral DNA? Many scientists felt that the classification
of risk presented to them was somewhat arbitrary. Some were totally against all
controls on research, but these wore in a minority as most realised that if
biologists did not limit themselves, then the government, having now been
alerted, would legislate quickly and probably harshly. This view was mainly
American, the Eng1ish being conditioned to intervention from above in the form
of the Science Research Council.
Gradually the leadership of Paul Berg began to take effect,
and votes were taken on parts of the statements submitted to and altered by the
conference. A classi-
-6-
fication system was evolved and sent to NIH for review and
an account of the conference sent to Science (published in vol 107, pp991—995,
June 1975).
The statement said in part, “the evaluation of potential
biohazards has proved to be extremely difficult. It is this ignorance that has
compelled us to conclude that it would be wise to exercise considerable caution
in performing this research ... most of the work on construction of recombinant
DNA molecules should proceed, provided that appropriate safeguards, principally
biological and physical barriers adequate to contain the newly created
organisms, are employed.” It stated that safeguards should be over—protective
initially and reduced as necessary when the true risk should be known. The
level of containment should match the estimated risks, as far as that could be
determined. As risks were higher with larger volumes small scale experiments
should be encouraged. (This section effectively blocking industrial
exploitation of gene products.)
The containment system involved a twofold classification:
That of physical containment, ranging from a standard microbiological
laboratory (class P1) to a laboratory of the type originally equipped for
biological warfare (P4), such as Fort Detrick in the USA and Porton Down in
England. The second type was of biological containment, involving the
production of crippled bacteria and plasmids (host/vector systems) which if
left outside a lab environment would not replicate or survive long enough to
pass on their DNA. This system was at that time purely hypothetical. Each
possible experiment was to be assigned a place in these systems, running from
minimal risk (P1 + EK1 where EK1 is the use of standard E. coli K12) to very
high risk (P3 + EK3, a severely crippled strain proven to be unable to survive
outside the lab), which was at that time an impossible experiment.
Since this self regulation was a purely unselfish act it was
not surprising that a politician would misunderstand the motive. Senator Edward
Kennedy, a man of great influence in Congress, was Chairman of the Senate
Subcommittee on Health. In April 1975, he convened a meeting at which he
questioned a panel of four people about the Asilomar Guidelines and how they
were arrived at. After Stanley Cohen had explained the basics of the subject to
the Senator, Kennedy asked him about possible theft of hybrid plasmids. He was
obviously thinking about the theft of fissionables, now a major worry in the
other Nuclear Debate; it took some explaining that plasmids could not be
counted or weighed and the only possible check was to limit the number of labs
working with the plasmid. He then abruptly changed the subject. (Biohazard
p149)
Kennedy later delivered an address at the Harvard School of
Public Health and delivered an attack on the Asilomar Conference, calling it
"inadequate" and saying
—7—
that “scientists alone decided to impose the moratorium and
scientists alone decided to lift it.” David Baltimore said of the speech, “We
weren't arguing that Asilomar was the last word - but at that time we were the
only ones that knew what was going on, and our whole point was to alert the
public. (Biohazard p156)
Kennedy later signed a Bill to restrict the
research.
After Asilomar, the NIH held meetings in San Francisco and
Woods Hole to assign categories to experiments. After the latter, a storm of
protest arose. The guidelines produced were less strict that those of Asilomar.
They were described as “Quite likely to draw the charge of self—serving
tokenism.” A petition of 50 bacteriophage workers was sent to DeWitt Stetten,
the committee chairman, beginning; “We are concerned that the present draft
appears to lower substantially the safety standards set and accepted by the
scientific community...at Asilomar.” (Playing God, p125) The media took up the
outcry and a further meeting was planned at La Jolla, California, in December.
By the time the La Jolla meeting, took place, American
recombinant DNA research was suffering badly. The moratorium was still in force
except where the Asilomar Guidelines were considered detailed enough, and this
was rarely. Most work still continued was the drive to produce disabled vectors
and hosts and was proving more difficult to accomplish than the Asilomar Group
had believed. Overall was the fear that if acceptable rules were not produced
soon then legislation - by such Antis as Senator Kennedy - was inevitable. The
British situation was not any better. The Williams committee was still
considering the evidence, and until the report was published very little work
could proceed. The rest of Europe, in the main, waited for the European
Molecular Biology Organisation (EMB0) to form a decision making committee, and
as far as can be determined, kept to the moratorium.
At La Jolla, three sets of guidelines were to be discussed.
and synthesised into a document satisfying everyone. Once again, points of
disagreement arose immediately. Does a regulation forbidding release of
recombinant DNA into the environment include new nitrogen fixing plants? How
pure is “highly purified”
DNA? What is an acceptable demonstration of "characterised"
DNA? To imagine part of their deliberations - Reptilian DA will not have a high
likelihood of containing proteins affecting humans. However what about other
animals coming into contact with expressed reptilian DNA in E. coli? If the DNA
is from a snake, how can it be purified in order to exclude venom genes?
Perhaps it will be useful to clone venom genes, and in this case, to what
higher category should the experiment be assigned? If it proves impossible to
clone in E. coli due to a weakness, say of the cell wall, and a more vigorous
or pathogenic bacterium must be used,
could this experiment still be allowed?
—8—
For every DNA discussed a similar set of considerations must
be taken into account.
A few days before the La Jolla meeting, a workshop was held
at Torrey Pines, Calif. called the Design and Testing of Safer Prokaryotic
Vehicles and Bacterial Hosts For Research on Recombinant DNA Molecules".
As an example of the success of physical—only containment, Fort Detrick (the
highest containment facility in the States) had had 423 hospitalizations and 3
deaths during its period as a biological warfare centre - about 30 years.
(Biohazard p 116) This was while working with strains of known pathogenicity.
How much more lax were workers going to be when working with E. coli differing
from the norm in only a short strand of DNA? At the meeting Berg stated “I’m
convinced that physical containment is overrated.” Discussions took place on
the possibility of using other organisms besides E. coli, the possibility of
building temperature sensitive bacteria which would die if introduced into the
human gut, and the like. The only positive advance discussed at the workshop
was made by Dr. Roy Curtiss who had crippled an E. coli K12 which; required
many nutrients, could not transfer its DNA, and was unable to survive at
mammalian body temperatures. This was to be discussed at the next meeting of an
NIH committee, in order to determine if it was suitable for EK2 status. Here
Sydney Brenner made one succinct point; would NIH be able to afford the time
and money to assess every new host/vector system as they began to be presented
to them?
Almost simultaneously, the final versions of the Eng1ish and
American guidelines were prepared and published. In the middle of 1976, the
Williams Report was published. The report called for legislation to be prepared
along the lines which it recommends. The main features of the report are: That
a body to be known as the Genetic Manipulation Advisory Group (GMAG) should be
set up, comprising a committee to advise and monitor each research project.
Instead of drafting inflexible guidelines, GMAG would consider each case on its
own merits, gradually building up a body of case law. However, guidelines are
included in the report, classifying experiments phylogenetically, into a series
of 4 categories. The categories are based mainly on physical containment, each
experiment being lowered 1 category if a disabled host/vector system is used.
There is another subdivision into random or purified DNA, and if the DNA used
in purified non—pathogenic, then the system is lowered one category.
The guidelines are, however, not at all exclusive, and discussion
with GMAG and local safety officers and committees are an integral part of
them. The actual report is 32 pages long, mainly consisting of what comprises
the lab containment of each category. (CMND 6600 HMSO August 1976)
—9—
The report was incorporated into legislation in force by the
end of 1976, and although GMAG did not become a legal entity until 1978, it
began operation before then.
On June 23rd, 1976, Dr. Frederickson of the NIH issued the
finalized guidelines, somewhat stricter than the Asilomar conference and the
following meetings had required. Dr. DeWitt Stetten described them as “in no
way opening the floodgates - rather a closing of leaks (in the Asilomar
guidelines)” The guidelines are much more detailed that those of the Williams Committee,
running to over 200 pages and including sections on the requirements of
containment levels, training of lab workers, the constitution of the NIH
committee, and appendices on the use of Bacillus subtilis in recombinant DNA
research, a report on safety practices in the lab, rules for the care of
experimental animals, and the quantity of proprietary bleach needed to
sterilise a spill.
As to the administration, the regulations state that the
institution to which the NIH grant is made is responsible, via the principal
investigator, for determining the level of containment and training the staff
to that level. A Biohazard Committee should be set up in each institution,
composed of sufficiently qualified people. (NIH Guidelines for Research
Involving Recombinant DNA Molecules, June 23rd 1976, US Government Printing
Office.)
While the predictable furor (in either camp) over these
guidelines was still continuing, the NIH committee met to consider the various
hosts and vectors developed for EK2
status. Dr. Curtiss’ E. coli phi 1776 was passed as EK2 , when used with two
plasmids, PSC1O1 and ColE1 Kan. A strain of Lambda developed by Phil Leder was
also passed for use with 1776 in this system. (Nature, 262, p2.)
In the City of Cambridge, Mass., a new type of incident
occurred, when Mark Ptashne of Harvard submitted a request to his superiors to
have several rooms converted to a P3 facility. The buildings are old, infested
with cockroaches and ants able to chew their way into labs and feed on any
material left on the lab benches. Although many of the staff at Harvard were in
disagreement, the local biohazard committee approved the move. This prompted
some people to go and see the Mayor, Alfred E. Vellucci, who misunderstood and
went away with the idea that the researchers were going to create “things that
crawl and things that creep” - which must have been a reference to the
cockroaches - and further fueled by a newspaper report, he called a council
meeting on June 23rd. Vellucci was not noted for his pride in having two such
establishments as Harvard and the Massachusetts Institute of Technology within
his city. He accused the head of the biohazards committee of not consulting him
or the people (which was denied) and demanded a shutdown on all recombinant DNA
research in the city, including that which was
—10—
already going on. To cut the story short he allowed a
cooling off period of 3 months during
which there would be a “good faith” moratorium, and spent his time collecting
facts. On July 7th a council meeting limited the moratorium to P3 and P4
research. In a subsequent vote a “Cambridge Laboratory Experimentation Board”
was set up, following the NIH rules but with certain extra powers. He later
took his grievances to a meeting of Mayors, and urged them to do likewise.
(Nature 262 p163 ). Vellucci’s attitude is understandable had this been a small
southern town, but is surprising at Cambridge. The real danger was that other
cities would take up his witch—hunt against scientists, leading to a welter of
city, State and Federal laws enclosing scientific research.
By February, 1977 this situation had almost come to pass.
The State Assembly of California had drawn up a set of guidelines for use in
the State which had had 4 readings before it heard that the State Dept. of
Health had its own and was preparing to implement them. There was a bitter
exchange over the 'ownership' of scientists. Senate and Congress had several
bills before them, one by Carter, and one by Kennedy, and others. (New
Scientist, l7th Feb, 374 and 17th Mar, 640) However, some of the Bills did not
make it by the end, of the session, and in September, they received a severe
setback. Senator Kennedy changed his position after receiving evidence from a
risk assessment meeting at Falmouth, Mass.. Although the evidence convinced
Kennedy, the cautious statement that perhaps the risks were not as high as had
been at one time believed, was described as a “scandal” and “misleading and
incomplete” by Jonathan King of Science For the People. Kennedy then went on to
suggest a commission be set up, including himself, The Assistant Secretary for
Health, and the Chairman of the Institute of Medicine. (New Scientist, 6th Oct
1977, p 219)
Reported later that month (New Scientist 27th Oct p219), was
a report that ‘natural’ gene engineering occurs in sewage. An outbreak of
porcine diarrhoea occurred which proved to be due to the linkage of an
enterotoxin gene with a multiple drug - resistance plasmid. This event added
weight to the growing feeling that most recombinant DNA molecules have been
tried by nature at some time and in most cases discarded.
Since by late 1977 the issue of experimental regulation had
been settled (except in the eyes of a vociferous minority), the emphasis
shifted to the administration of the bodies formed. Much of the debate centered
on secrecy. In December 1977 GMAG held a meeting to discuss confidentiality.
The Chairman, Sir Gordon Wolstenholme, had drawn up a document as the matter of
patents arose. Since any work had to be reported to the GMAG, any ‘leak’
through the group could lead to a loss of patentability. The legal aspect -
whether a bacterium producing a protein was a patentable device - was a
secondary though hotly contested argument.
—11—
When GMAG became a legal entity in 1978 each member would
have to sign the Official Secrets Act, although by the Health and Safety at
Work Act 1974 information could be disclosed if anyone's health was at risk.
Wolstenholme furthermore had a list of business interests of the members of
GMAG, and saw to it that only
disinterested people attended a given meeting. (NS 76 1977 p397)
In late 1978 in America, the debate centered upon excessive
secrecy. Joseph Califano, the Secretary
of Health, Education and Welfare, emphasised the need for public participation.
“The decision making process must be done democratically not by special debates.” However, when a
proposal for the revision of the NIH guidelines was discussed, it was confined
to those in “biomedical circles”. All who testified in support of the proposed
revisions were of the field. The lawyer, Professor Boreano, accused the NIH
committee of being an “old boys' network” and a report by Nancy Pfund showed
that 70% of the members of the Institutional Biohazard committees were in
microbiology, biochemistry and molecular genetics. Frederikson’s proposals
to “broaden (the committee) modestly as needed for expertise” and to “include,
perhaps, a dissenter from NIH policies” were described as inadequate. To a
certain extent, this was taking place in Britain, where ASTMS member Donna
Haber declared “even cleaning ladies have a part to play”. (Nature 12th Oct,
1978 p468).
In August 1978 a substantial revision to the NIH guidelines
was proposed. After public and private
discussion the new guidelines came into force just before Christmas. The new
system meant that almost every kind of experiment was downgraded one step, and
several kinds were exempted altogether. The exemptions included:
Work with naked DNA, which is considered unlikely to be
harmful
Recombinant DA from a single non—chromosomal or viral source
Recombinant DNA from one organism when propagated only in
that organism
Recombinant DNA from species within the following list:
Escherischia Spp.
Serratia Spp.
Edwardiella Spp.
Enterobacter Spp.
Erwinia Spp.
Citrobacter Spp.
Pseudomonas Spp.
Salmonella Spp.
Rhizobium Spp.
Klebsiella Spp.
Shigella Spp.
Acinobacter calcoaceticus
Agrobacteriim tumifaciens
Rhodopseudomonas spharoides
Also Local Biohazard Committees were renamed
"Biosafety" committees. Dr. Prederickson.
—12—
finally stated: “While it is true that other techniques in
genetic research, such as cell fusion and chromosome transfer, may result in
the formation of recombinant molecules, I don't believe at this time we should
mandate or extend the guidelines to research in these areas.’ (Nature 10th Aug
1978 p411)
When the guidelines were released Califano stated that they
were a reflection of decreased concern within the scientific community, and
also partly because research in America was being held up compared with that in
laxer countries. On the implementation of the guidelines, new systems of
organisations for the various governing bodies were announced giving a much
larger share of the decision making to laymen with other skills, such as
lawyers. This was due to a review presented by the DHEW’s General Council, Mr.
Peter Libassi. (Nature2l/28 Dec. p 744 & NS 4th Jan 1979) At the same time,
Califano found a way to bring industry within the guidelines. He instructed the
Food and Drug Administration and the Environmental Protection Agency to use
their statutory authority “to require that recombinant DNA research conducted
by the private sector complies with the NIH guidelines.”
This change left Britain in a position of repression
compared with the USA, a situation still found at the conclusion of reading for
this review. The situation is so awry that GMAG were on the point of
instructing researchers to notify them if performing a self—cloning (coli—coli)
experiment, whereas in the States a lab may clone shotgunned genes of a
plant—tumour forming bacterium in coli without any restrictions.
However, a completely new system of classification has been
proposed, entirely different from the old phylogenetic approach. This risk
assessment analysis involves a mathematical consideration of the possibility of
escape or danger at every step - eg, Escape from containment, persistence in
the environment, access to risk and the reduction of risk factors. The
unveiling of this system caused some disquiet, as many believe that more must
be known about the risks before we can start multiplying them together.
However, GMAG have agreed to institute the system for a trial period of one
year. (Nature 276, 104-7)
This then, is the situation up to April 1979 in Britain and
America.
—13—
GENETIC RESEARCH IN OTHER COUNTRIES
Little can be found in the standard literature about the
controls of communist countries, and not much more on the European communities.
A review in New Scientist gave the following information on
the European situation. Despite their relative inactivity in the field the
leaders were invited to Asilomar. On returning, what research was being done
continued under the Asilomar guidelines. By 1975, the French authority, the
DGRST, set up two committees, one to look into the ethical side of the work and
one to regulate experiments. In Germany, the DFG met in June 1975 to discuss
the situation, by which time Holland and Sweden had formed their own
committees. By March 1977 official action had. been taken in Belgium, Denmark,
Norway, Switzerland, Israel, Italy and some others. The Soviet Union was
expected to draft guidelines by June, but no report of this has subsequently
been found.
Most European countries accepted the provisional NIH
guidelines while waiting for the Williams Report. After both were available,
they were faced with a choice of one or a synthesis of the two. As the two are
by no means identical, this led to a situation where a researcher would
telephone colleagues in another country and ask if a particular experiment may
be performed there. There are several international bodies, the European
Molecular Biology Organisation (EBO), the EMB laboratory, and the European
Science Foundation (ESF). The EtBO committtee recommended a synthesis of the
two, and it and the ESF agreed that each country should establish a national
committee. Following the issuing of the new laxer American guidelines, most
European countries followed, leaving Britain with the harshest legislation in
the west. (NS 10th March 1977 p592-4)
In January 1979, the EEC was left considering a suggestion
from its commission that genetic engineering be considered hazardous and that
each practitioner be registered and approved by the appropriate national
authority in each member state. “To request,” says the report, “statutory
controls and legislation does not constitute an aggression to progress, but, on
the contrary, a recognition of the need to adapt society to new scientific
developments. (NS 4th Jan 1979)
—14 —
DISCUSSION
THE SAFETY OF GENETIC ENGINEERING
From the time of the Asilomar Conference, it has been
suggested that the best way to asses the risk is to perform the “ultimate
experiment” that is, to obtain a newborn germ—free mouse, and to infect it with
bacteria, or phage, containing DNA from the tumour—producing mouse polyoma
virus, and finding of tumours subsequently would prove the risk of working with
recombinant DNA from viruses.
Both Porton Down and Fort Detrick instituted experiments in
their P4 labs, but only one result has been announced. The National Institute
of Allergy and Infectious Diseases inserted Mouse Polyoma Virus into a phage and
injected it into mice. It was found that if only one copy of the viral genome
was present, no tumour would develop, but if two were present in tandem, then
two out of five of the mice developed tumours. (Nature l5th Feb, 1979) This
result would seem to show that the shotgun method of preparing DNA may in fact
be less dangerous than purifying genes before insertion.
According to Jonathan King, very many infections are caused
by E. coli, usually in people weakened by a previous illness. Blood infections
and meningitis are among the diseases aggravated, and King estimates that
10,000 deaths a year are partly caused by E. coli complications. His point is
that if a coli carrying the gene for insulin or oestrogen should get into the
body, what would the consequences be? (Nature 276 ., Nov 1978) However, E. coli
seems to pose little threat to healthy people. Dr. Charles Weissman swallowed a
considerable amount of Kanamycin—resistant E. coli containing a marked plasmid.
Three days later there was no sign of the plasmid, although the Kanamycin
resistant strain of E. coli lasted until an attack of diarrhoea flushed it out
of his system. (Playing God, p118—9)
In early 1977, there was an explosion in a biology lab at
the university in Pittsburgh. David Baltimore suggested that the explosion was
too severe to allow any organisms to survive, but as Friends of the Earth pointed
out, there no provisions for this in the guidelines, beyond a stipulation that
no lab should be adjacent to a store of inflammable materials. (NS Jan 26th,
1977)
Chargaff and Sinsheimer take the view that planting
eukaryote genes in bacteria is “betraying state secrets at the molecular level”
and may lead to prokaryotes with dangerously increased infectivity. This poses
“incalculable evolutionary dangers”. However, this not a popular view, as many
people believe that most combinations of genes have been tried by nature in the
past, and if they do not exist now, it is because they have no advantage.
—15—
I personally believe that the dangers are overrated and
remain undemonstrated. The research is not only a race to keep up with the
Russians, but also a tremendous possibility for good. Unlike James Watson, who
underwent a change of heart since his signing of the Berg letter, I do not
favour a removal of all controls from the research, though I do feel that
genetic engineering is an area unfairly singled out by people overawed by a
technological society and looking for someone to blame.
THE FUTURE
One can only hope that further work will be done on finding
a host/vector system not so closely associated with man, if possible one with a
severely restricted environment. Crippled E. coli, such as phi 1776, may have
little chance of surviving outside the lab, but by all accounts it is difficult
to keep it alive inside.
Some are inclined to believe that eukaryotic cells provide
the answer. Yeast, Saccharomyces cerevisiae, would be an ideal system. Reports
on the possibility of using yeast are beginning to filter in. Hennan, Hicks and
Fink succeeded in transforming yeast sphaeroplasts using a ColE1 plasmid, and
reported that the plasmid integrated on the yeast chromosome, though the latter
is in some doubt. While yeast is easy to culture and does not inhabit people
and animals, there is still a tremendous amount of work to be done before it
could ever be as useful as E. coli.
—16—
REFERENCES
BOOKS:
Biohazard by Michae1 Rogers, Knopf, New York 1977
Playing God by June Goodfield, Hutchinson and Co, London
1977
REVIEWS:
The Recombinant DNA Debate, Scientific American 22—34 1977
REFERENCES QUOTED IN THE TEXT :
Letter, Science 181 1114, 1973
Letter, Science July 26th 1974
Letter, Nature 174 July 1974
Letter, Science June 1975, pD99l—995.
Nature, 262 p2 1976
Nature, 262 p163 1976
New Scientist 17th Feb 1977 p374
New Scientist 17th Mar 1977 p640
New Scientist 6th Oct 1977 P219
New Scientist 76, p397 1977
Nature 12th Oct p468 1978
Nature 10th Aug 411 1978
Nature 21/28 Dec p744 1978
New Scientist 4th Jan 1979
Nature 276, 104—107 1979
New Scientist 10th Mar 1977 p592—594
New Scientist 4th Jan 1979
Nature 15th Feb 1979
Nature 276, Nov 1978
New Scientist Jan 26th 1977
Clarke and Carbon, Proc. Nat. Acad. Sci. 72 4361—4365 1975.
NIH Guidelines for Research Involving
Recombinant DNA Molecules, June 1976
US Government Printing Office.
The Ashby Report on the Experimental
Manipulation of the Genetic Composition
of Micro—organisms, CMND 5880 HMSO 1975
Report of the Working Party on the Practice of Genetic
Manipulation, CMND 6600, HMSO Aug 1976
Background material mainly from the two books, Molecular
Genetics lectures,
Editorials in the Weeklies. Acknowledgements for help and
advice from Charles
Weiner of Massachusetts Institute of Technology and from Jon
Beckwith of Harvard Medical School.
(Cleared up some scanpos, removed university name - Queen Mary College - as article was not run by school's legal before posting 06/25)
