Nottingham, Stephen.Eat Your Genes: How Genetically
Modified Food Is Entering Our Diet. New York: Zed
Books, 1998. A broad but detailed overview of the
science, business, and ethical concerns regarding
GM foods. For the general reader.
Charles L. Vigue
See also Agriculture in Canada; Agriculture in the
United States; Food trends; Genetic engineering;
Genetics research; Organic food movement; Sci-
ence and technology.
Genetics research
Definition Scientific investigations of the role,
function, and manipulation of the biochemical
mechanisms governing heredity and variation
in organisms
Scientific research during the 1970’s and 1980’s produced
the laborator y technology that made possible the advances of
the 1990’s, including the first successful cloning of a mam-
mal, genetically engineered crops, and the launch of the
Human Genome Project.
During the 1990’s, techniques such as deoxyribonu-
cleic acid (DNA) sequencing became common-
place, and the order of nucleotides in the DNA from
organisms as diverse as bacteria and human beings
was largely determined. The technology of animal
cloning reached the stage that it became theoreti-
cally possible to even clone a human, setting in mo-
tion a controversy that continued into the early
twenty-first century. The ability to isolate specific
genes resulted in the production of genetically mod-
ified crops, technology that could be applied to feed-
ing the hungry or to the creation of “super-weeds.”
The ethical limits to which scientists could approach
were no longer confined to science-fiction movies.
Animal Cloning While any attempts to clone a hu-
man being would clearly create overwhelming con-
troversy, and indeed was not even seriously dis-
cussed, the possibility of cloning animals was much
more realistic. The experimental basis for animal
cloning involved removing the nucleus from an
adult cell obtained from the animal and using it to
replace the nucleus from an embryonic cell. The
adult nucleus was diploid, meaning it contained
pairs of chromosomes as found in all somatic cells;
the genetic content itself would pose no problem.
The question was whether that cell could survive and
be stimulated to replicate and differentiate, ulti-
mately producing a viable animal that would be
identical to the animal that provided the nucleus.
The scientific background for such experiments
dated to the work of British biologist Sir John
Gurdon in the early 1960’s. Gurdon, working at Ox-
ford University, demonstrated the viability of nu-
clear transfer experiments using embryos from
Xenopus, a genus of clawed frogs. While Gurdon had
been successful in the cloning of tadpoles (even
these never fully developed into frogs), attempts to
clone other animals had failed, and many scientists
felt that attempts to clone animals more evolution-
arily advanced than frogs would only result in fail-
ure. Gurdon’s work did result in the addition of a
new word to the lexicon of animal biology; the Brit-
ish geneticist J. B. S. Haldane referred to the tad-
poles as “clones.”
In fact, most such attempts to clone mammals
had proven unsuccessful; over 270 attempts at clon-
ing sheep were ultimately carried out. However, in
1996, Ian Wilmut and Keith H. S. Campbell at the
Roslin Institute in Scotland carried out the first such
successful experiment in cloning. The nucleus from
a mammary cell obtained from a sheep had been
transplanted into an enucleated oocyte. The cell was
stimulated by electric shock and implanted into the
uterus of a ewe. In July of that year, the first cloned
sheep was born and named Dolly—in honor of en-
tertainer Dolly Parton. Dolly lived six years and suc-
cessfully mothered four lambs of her own. Her rela-
tively early death for a sheep, a consequence of lung
infections normally found in older animals, gave rise
to concerns that since she had been produced from
an adult cell nucleus, Dolly was actually a young
sheep with the genetic characteristics of an older an-
imal.Human Genome Project Arguably the most ambi-
tious genetics project was the decision to attempt the
sequencing of the complete human genome, a proj-
ect called the Human Genome Project. The plan of
procedure had its origins in the late 1980’s, when a
decision was made to carry out collaborative re-
search among a number of universities and research
centers around the world. The original outline envi-
sioned a fifteen-year endeavor, with a synopsis of
progress to be reported at five-year intervals, begin-364 Genetics research The Nineties in America