SKIN DEEP.

• Author: ANGIER, NATALIE
• Position: DNA analysis provides few clues to racial identity

Do the races really differ? Not in any scientific way, says the latest evidence from the human genomic project.

You know that person next to you in class, or on the bus, or in the movie ticket line, the one who is of a different race, and maybe in your secret heart of hearts you think is in some way just different from you because his or her skin color is different?

Think again. You share 99.99 percent of the same genetic material with that person. In fact, chances are that you are as genetically different from your friends of the same race as you are from anybody of another race.

Scientists have long suspected that the racial categories recognized by society are not reflected in human genes--the bits of material at the core of human cells that order the chemical reactions that give you your traits, ranging from height to eye color to a tendency to like 'N Sync. But the more closely researchers examine the human genome--the name for the package of genetic material individual to each human--the more most of them are convinced that the standard labels used to distinguish people by "race" have little or no biological meaning.

YOU ARE THEY, AS THEY ARE YOU

While it may seem easy to tell at a glance whether a person is Caucasian, African, or Asian, the ease dissolves when one probes beneath the surface and scans the genome for the hallmarks of race in DNA, the protein molecules that make up genes.

As it turns out, scientists say, the human species is so young in its evolution, and its migratory patterns so wide and restless, that it has simply not had a chance to divide itself into separate biological groups or races in any but the most superficial ways.

"Race is a social concept, not a scientific one," says Dr. J. Craig Venter, one of the two scientists recently credited with mapping the entire human genome. "We all evolved in the last 100,000 years from the same small number of tribes that migrated out of Africa and colonized the world."

Venter and other researchers say the genome demonstrates there is only one race: the human race. The traits most commonly used to distinguish one race from another, like skin and eye color, or the width of the nose, are controlled by a relatively small number of genes, and thus have been able to change rapidly in response to extreme environmental pressures during the short course of Homo sapiens history. Equatorial populations evolved dark skin, presumably to protect against ultraviolet radiation, while people...