January
29, 2001
Race
and the Human Genome
By
Hisham Aidi
Last
November, Nobel Laureate James Watson, the man who discovered the double
helix structure of DNA in the 1950s and started the international Human
Genome Project in 1990, sparked outrage when he suggested that there could
be biochemical links between skin color and sex drive. Speaking at a seminar
at the University of California Berkeley, "the father of DNA" argued that
exposure to sunlight can increase a person's sexual appetite.
"That's why you have
Latin lovers," Watson said. "You never hear of English lovers, only English
patients." Watson referred to an experiment in which male subjects (rats
and humans) were injected with melanin and immediately developed erections.
Although the esteemed scientist claimed that his findings were the product
of documented research, many in the scientific community and beyond were
appalled by Watson's remarks.
Theories of genetic
differences between races have a long and troubling history and are unsettling
to many today. And the political implications of such ideas are, of course,
incendiary.
In his State of the
Union address in January 2000, President Clinton attempted to allay people's
fears about the dangerous and unethical potential of recent advances in
genetic science. "We are all, regardless of race, 99.9 percent the same,"
he declared.
Mindful of the ways
in which research on human genetics has historically been abused, Clinton
was trying to reassure a public alarmed by the tremendous strides made
by scientists who announced that they had completely sequenced the human
genome last year. The potential for misuse of this exploding field of
research is clear: colonialism, slavery, apartheid and the Holocaust,
for example, were all justified by pseudo-scientific evidence that certain
groups are genetically inferior to those who were said to be genetically
destined to dominate.
More recently, this
perspective informed the work of Charles Murray and Richard Herrnstein,
whose notorious The Bell Curve, which examined 80 years of data
on human intelligence, concluded that although every American ethnic group
showed the same distribution in IQ, their averages were different, with
African Americans possessing an IQ average 15 points lower than whites.
Murray and Herrnstein stated that this difference could not be explained
by environment alone, that African Americans' genetic constitution also
played a role.
But while conservatives
and liberals alike have argued against the very idea of genetically-dictated
racial differences, some scholars feel that the "politically correct"
emphasis on the genetic similarities between people of different ethnic
groups has stifled potentially useful research into actual distinctions
that do exist between and within genetic populations.
"In effect, he [President
Clinton] was implying that there are no meaningful differences between
populations. That belief is wrong and dangerously so," wrote Jon Entine
in the San Francisco Examiner. "We share 98.4 percent of our genes
with chimpanzees, 95 percent with dogs, and 74 percent with microscopic
roundworms. Only one chromosome determines if one is born male or female.
There is no discernible difference in the DNA of a wolf and a Labrador
retriever, yet their inbred behavioral differences are immense. Clearly,
what's meaningful is which genes differ and how they are patterned, not
the percent of genes. A tiny number of genes can translate into huge functional
differences."
According to an editorial
in the British paper The Independent, a fear of offending members
of historically stigmatized racial groups has prevented us from confronting
the evidence that tiny genetic variations do actually account for real
physical and behavioral differences. "We have gone from one kind of ignorance
and prejudice to another without walking the road of good sense," wrote
the anonymous commentator. "There are important biological differences
that distinguish groups and individuals within groups. Vastly more African
American men have prostate cancer than do white men. British Asians have
significantly higher rates of heart disease...If gene research is only
allowed among white groups, important breakthroughs will only be available
to them, too."
Not to explore genetic
differences and genes responsible for certain diseases that afflict different
ethnic grips, is, as London Times journalist Anjana Ahuja writes,
"to leave ethnic groups in the grip of disease for the sake of political
correctness."
Entine, author of
Taboo: Why Black Athletes Dominate Sports and Why We Are Afraid to
Talk About It, makes a similar point. "Although we share a common
humanity, we are different in critical ways such as our genetic susceptibility
to diseases," he says. "For instance, blacks are genetically predisposed
to contracting colo-rectal cancer; Eurasian whites are genetically prone
to multiple sclerosis -- and Asians are by and large victims of neither.
The problem with Clinton's pandering to political correctness is that
it threatens confidence in the life-saving aspects of the genetic revolution."
While genetic research
may reveal more variation within the human family than many may wish to
acknowledge, it can also demonstrate specific genetic advantages that
certain populations may have, possibly yielding discoveries that could
benefit humankind as a whole. Yet, scholars argue, many people seem more
comfortable with the notion of genetically-determined diseases than they
are with the idea that particular groups may also possess specific genetic
gifts.
"Why do we readily
accept that evolution has turned out blacks with a genetic proclivity
to contract sickle cell, Jews of European heritage who are one hundred
times more likely than other groups to fall victim to the degenerative
mental disease Tay-Sachs, and whites who are most vulnerable to cystic
fibrosis, yet find it racist to acknowledge that blacks of West African
ancestry have evolved into the world's best sprinters and jumpers and
East Asians the best divers?" Entine asks rhetorically.
Along similar lines,
Professor Clive Harper of the University of Sydney, Australia claims to
have found that among Aborigines, the area of the brain responsible for
visual processing is 25 percent larger than average. Harper's as yet unpublished
studies indicate that Aboriginal children have photographic memories,
an evolutionary gift from their ancestors, who "had to master the vast
landscape to survive."
While examining genetic
advantages in key populations can teach lessons about evolution, scientists
argue that studying genetic illnesses and their development can also lead
us to potential treatments.
"I believe that we
need to look at the causes of differences in diseases between the various
races," writes Claude Bouchard, a geneticist at the Pennington Biomedical
Research Center at Louisiana State University who studies obesity and
athletic performance, in the American Journal of Human Biology.
"In human biology...it is important to understand if age, gender, and
race, and other population characteristics contribute to phenotype variation.
Only by confronting these enormous issues head-on, and not by circumventing
them in the guise of political correctness, do we stand a chance to evaluate
the discriminating agendas and devise appropriate interventions."
The alarm of those
who are disturbed by Western science's rush to decode the human genetic
cipher is perhaps well-founded. In addition to the eugenics experiments
of 20th century scientists intent on demonstrating African genetic inferiority,
reports of even more sinister applications of the new genetic research
abound. In apartheid-era South Africa, for example, government scientists
are said to have conceived and experimented with weapons designed to genetically
target blacks, leaving whites unharmed. Most scientists, however, feel
that such unethical activities are unlikely.
"We're not in the
business of designing smart bombs to wipe out races," Spencer Wells, a
population geneticist at Oxford University who studies the genes of different
ethnic groups, told the London Times. "People talk about the history
of eugenics, and a lot of early research in this country was pretty serious,
but we are not doing this to develop people along racial lines. Our species
has a single, shared history, and we ought to learn what it is."
The Human Genome Project
thus far has revealed that roughly 99.9 percent of the DNA of every person
on the planet is identical. Human variation, in height, skin color, and
so forth, is actually determined by a tiny fraction of the genome. And
genetic variations within ethnic groups are wider than those between different
groups. Wells, who has studied 200 different genetic markers on the Y
chromosome in samples from different areas of the world, argues that most
people have multiple markers reflecting extensive migration and intermarriage,
though ultimately, we all carry in our genes the traces of African ancestry.
As Professor Chris Stringer of London's Natural History Museum says, "We
are all African under the skin."
Geneticists, says
Wells, do not subscribe to the concept of a biology of race. "You can
find more genetic differences between two Africans than between an African
and commoner from the Outer Hebrides," says Wells. "To me, race is a cultural
construct. I put it another way: there is genetic variation among geographical
groups." Wells speculates that the characteristics generally associated
with race, such as skin color, account for no more than a tenth of the
variation between humans, which is 0.01% of our genetic make-up.
Experts argue that
differences in skin color — the most obvious difference between
population groups -- developed as people migrated from Africa to colder
environments, with paler skins developing in colder regions to "allow
more efficient production of vitamin D from sparse sunlight," while people
near the equator developed dark skin to protect them from the sun's harmful
effects.
While recent genetic
research has appeared to undermine the notion of "race" as a biologically-defined
category, concern that scientific inquiry will be used to justify racism
has proven an obstacle to popular acceptance of the study of the human
genome. "If we do not welcome the impending genetic revolution with open
minds, if we are scared to ask and to answer difficult questions, if we
lose faith in science, then there is no winner; we all lose," says Jon
Entine. "The question is no longer whether genetic research will continue
but to what end."
In fact, recent research
has actually debunked theories of a genetic racial hierarchy. In one study,
James Flynn of the University of Otago in New Zealand forcefully exposed
The Bell Curve's shoddy reasoning, arguing that the IQ scores
of today are significantly higher than those of previous generations and
that IQ test scores are influenced by environment as much as any genetic
factor. "An environmental explanation of the racial IQ gap need only posit
this: that the average environment for blacks in 1995 matched the quality
of the average environment for whites in 1945. I don't find that implausible,"
Flynn says. According to his findings, when other measures of intelligence
are taken into consideration, results are spread out more evenly across
ethnic groups, suggesting that there is a cultural bias in IQ tests that
works against certain ethnic groups.
Murray, The Bell
Curve's co-author, is unswayed and is adamant that genetic research
will validate his thesis. "Within the next twenty or thirty years, we're
going to know the whole genetic story about IQ," Murray told the London
Times. "It can't be held back. What we need to start saying now is
that we can look at these facts squarely in the face and not run screaming
from the room."
While advances in
genetic research and the mapping of the human genome could be used to
promote various theories of race, many scholars argue that only by continuing
to unravel the mysteries of genetic difference and evolution can we truly
understand the similarities and variations that exist within the human
family. What's more, warns Walter E. Williams of George Mason University,
"If decent people don't discuss human biodiversity, we concede the turf
to black and white racists."
© Copyright 1999-2000 Africana.com
Inc.
Hisham
Aidi is a freelance writer living in New York.
Photo:
A
scientist surveys a computer-generated model of a DNA molecule. (Corbis
Images)
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