The latest revelation about the conflict between Henry Louis Gates Jr. and Sgt. James Crowley is that the two men may be very, very distantly related. Late yesterday, ABC News reported that the professor and his arresting officer shared an ancestor in Niall of the Nine Hostages , a fourth-century Irish king whose blood, we are told, runs through up to one in 12 present-day Irishmen. Associated Content goes so far as to claim that the men are "actually cousins."
As this morning's " Google Trends " post noted, the DNA connection has since then become a public fixation. Why do we care? In Slate three years ago, Steve Olson explained that most people alive today, regardless of their races, have ancestors scattered throughout the world. Genetic tests can only measure lineage in a direct male line—father to father to father, all the way back. When you account for connections through women, though, "virtually everyone with any European ancestry" would be able count Niall of the Nine Hostages as an ancestor. In fact, Olson's research suggested that if any two people traced their lineage back to about 1,000 B.C., their ancestors would be identical.
Gates and Crowley's common DNA is not particularly unusual. What's stranger is today's obsession with these way-back family ties. Again: Why do we care? Are the thorny social and judicial questions framing Gates-gate softened by the fact the two men share genetics?
Behind today's interest in the "surprising" DNA connection, it seems to me, is a deeply unsettling public assumption about race as a biological measure of otherness. We know it isn't so: It's still unclear whether race can even be reliably determined from a given DNA sample. Yet a looming belief in biological difference (or, at least, surprise that black and white men should share genes) seems to linger. Had it been two pale-faced people found to have common origins—say, Vladimir Putin and Mikheil Saakashvili—would that news have likewise climbed the Google charts? It's hard to think so. A cultural idea of race as difference has caused enough problems. Seeing that idea show up in biological assumptions, too, is frightening.
Photograph of Henry Louis Gates Jr. by PETER KRAMER/Getty Images