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startlingly reminiscent of the traditional argument against evo-
lution that it is an assault on human dignity. That was pre-
cisely the text and heading of an open letter addressed to Presi-
dent George W. Bush in the Washington Times in January,
2002, signed by 29 conservative political and religious leaders.
The media have waged an energetic campaign against clon-
ing. We have examples in the 1976 novel, The Boys from Brazil
by Ira Levin, made into a film starring James Mason in 1978,
and most recently in 2002, with the appearance of Star Wars
Part II: Attack of the Clones. There is even a canard as to
whether human cloning methods might be patentable.
The New York Times is entirely correct: Opposition to re-
productive cloning is universal in Congress, and if any senator
or congressman secretly harbors a more benign view of the pro-
cedure, the chance that he or she will express that opinion pub-
licly is absolutely zero. In 2001, the House of Representatives
voted to ban all forms of cloning, but the Senate resisted a total
disallowment. Congress has thus resolved to criminalize repro-
ductive cloning, even though Congress s unanimity in this area
is not shared by everyone in the scientific and scholarly commu-
nity. According to the Wall Street Journal, some diplomats said
they believe the U.S. stand in the U.N. was primarily intended
to score domestic political points with religious conservatives
and antiabortion activists. But such moods are hardly limited to
the United States. On November 6, 2003, by a 80-79 vote, with
15 abstentions, the United Nations narrowly resolved to delay
by two years a vote supported by the United States and the
Vatican to outlaw both therapeutic and reproductive cloning. A
number of other countries supported a Belgian proposal to ban
reproductive cloning while permitting therapeutic cloning.
34 Science
Animal breeding methods usually amount to producing a
specific type on the basis of very strict characteristics. The same
is true for plant selection, in which a rich variety of strains is
usually replaced by a few monocultures. Nothing of the sort
would be appropriate for human populations. Human selection,
as proposed by proponents of eugenics, would be aimed at a far
more limited reduction in genetic variance. Diversity is not sim-
ply as a great source of strength but also as an integral part of
what we are and want to be. A certain reduction of this variabil-
ity, on the other hand, is the mathematical goal. Eugenicists ar-
gue that even a very significant channeling of motherhood and a
far more stringent selection among men would still leave billions
of people reproducing. By comparison, all thoroughbred race
horses stem from three Middle Eastern stallions, and natural
selection can be even more draconian.
Mapping the Human Genome
We have the intestines of chickens
to tell the fortunes of war.
We have slaves
that they might be silent.
We have stones
that we might build.
Why then should we trouble the gods?
Osip Mandelstam, Nature is the Same Rome&
Genetics is a very young science. The theory of evolution by
natural selection was not formally advanced until 1859. About
the same time the Austrian monk Gregor Mendel stumbled
onthe secret of creation when he published the results of his con-
trolled pollination of the garden pea, but his discoveries, pub-
lished in 1866, were ignored for the rest of the century, and
Darwin never learned of them. Even the discovery of the mecha-
nism of fertilization as a union of the nuclei of male and female
sex cells was not made until 1875; 1888 saw the discovery of cer-
tain deeply stained bodies in cell nuclei, which were christened
chromosomes, and in 1909 the word gene came to be applied
to the Mendelian factors of heredity. The first in vitro fertiliza-
tion (rabbit and also monkey) was not achieved until 1934, and
as for the double helical structure of DNA, its discovery dates
back only to 1953. This is all so recent that although early eu-
Science 35
genicists had set their goals and methods they were largely igno-
rant of the mechanisms involved.
The mapping of the human genome is still in an early stage.
The amount we don t know vastly dwarfs what we do know.
There appear to be approximately three billion bases, or chemi-
cal letters, making up the nucleotide sequences that form 20,000
to 30,000 genes which code directly for proteins. The mapping of
the human genome is now complete, but just how genes and the
proteins they produce interact is still poorly understood.
But protein-coding genes comprise only 2% of the human
genome. The functions of other DNA sequences are still largely a
mystery. We do know that some of them contain switches that
turn genes on and off, and we have learned that at the ends of
the chromosomes there are telomeres, whose shortening appears
to be related to the aging process, and nonfunctional genomic
parasites, whose only function in our bodies seems to be to repli-
cate themselves. An estimated 40-48% consists of repeat se-
quences. Even after sequencing the genome, we will still have to
determine how these data relate to expression. The sequences
are only the parts list to a grand machine, the outlines of which
we are only beginning to trace.
Scholarly opinion is rapidly growing more cognizant of the
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