New findings undermine scientists' claim that race isn't real
For years, mainstream scientists have said there are no real racial differences among people. Race is purely a "social construct"
– in other words, it's basically imaginary, they have argued.
But two new studies raise doubts about a key calculation on which this argument rests.
This calculation, often cited publicly by some of world's most renowned geneticists, is that all humans are
than 99.9 percent genetically
identical. As geneticist Eric Lander told Wired Magazine in February,
" more than 99.9 percent identical at the molecular level. Racial and ethnic differences are all indeed only skin deep."
Even U.S. President Bill Clinton
speech: "All human beings, regardless of race, are more than 99.9 percent the same."
But two new studies suggest that percentage is too high, researchers say
– although it's unclear
percent number is pure nonsense," wrote Michael Wigler, of Cold Spring Harbor Laboratory, New York, in a recent email. "I will not say anything more about it."
However, "it is true that humans are more like each other than many other species," he added.
Wigler is a co-author of one of the two studies, which is published in the July 23 advance online edition of the prestigious research journal Science.
In the study, the researchers wrote that they were surprised to find several large-scale, previously unidentified differences in human DNA. There is considerable structural variation in the human genome, most of which was not previously apparent by other methods of genomic analysis," they wrote.
Other researchers take a more moderate view of the findings. "Taking all types of DNA variation into consideration and looking at the entire 'content' of the genome, I would now say we are
percent identical," says Stephen W. Scherer of the Hospital for Sick Children in Toronto. Scherer co-authored the other study, whose conclusions were similar to the first one, and which was published in the Aug. 1 advance online issue of the research journal Nature Genetics.
Scherer declined to comment
mean race is real.
– a researcher who has been quoted in published reports giving the 99.9% figure, and who works with the Whitehead Institute in Boston
– didn't respond to phone calls and emails requesting comment for this story. His secretary said he has been abroad.
Also unreachable for comment was Craig Venter, chairman of the Institute for Genomics Research in Rockville, Md., U.S.A.
Genomics. He didn't return phone calls or
In an age where almost any discussion of race sparks controversy and recrimination, some other researchers contacted for comment for this story also didn't call back. They included some people who have argued the opposite case, that race is real.
In one of the new studies, Wigler's group sampled DNA from 20 people from around the world. They detected 76 major differences among the people, differences known as "copy number polymorphisms." This means that some sections of genetic code are repeated, but the number of repetitions vary among people.
This "could explain why people are different"
– although whether it in fact does explain it is unproven, said Scherer.
His team reached similar findings to the Cold Spring Harbor group. "At first we were astonished and didn't believe our results because for years we had been taught that most variation in DNA was limited to very small changes." Later Scherer discovered that a Havard University team was making similar observations, so the groups combined their data and reached the same conclusion, he added.
The Cold Spring Harbor team found that these changes affected the code for 70 genes. These included genes involved in Cohen syndrome
– a form of mental retardation
– as well as brain development, leukemia, drug resistant forms of breast cancer, regulation of eating and body weight.
The "race-isn't real" proponents have other arguments besides the 99.9% figure to back up their case. But that percentage figure has become one of the most prominent pieces of their argument since about four years ago, when the number came out from scientists associated with the Human Genome
Project, a 13-year program to map the human genetic code.
Another key argument that scientists have made to back up the statement that race isn't real, is that most of the genetic differences between people are local ones, not differences between "races." In other words, as the U.S. public television channel PBS states on its website: "two random Koreans are likely to be as genetically different as a Korean and an Italian."
However, those findings came out before the new genetic variation studies. Some researchers have suggested that the type of genetic variation these studies identified - the copy number differences - could be used as a new test for comparing the relative importance of local and group variation.
My guess is we will see all types of LCVs [large-scale copy variations], so there will be some population or group 'prevalent'" ones, Scherer said.
Whether or not race is real, researchers said, it doesn't mean one race is better than another. "Great abuse has occurred in the past with notions of 'genetic superiority' of one particular group," Stanford University's Neil Risch wrote in the July 1, 2002 issue of the research journal Genome Biology. "The notion of superiority is not scientific, only political, and can only be used for political purposes."