For years, researchers have been collecting DNA samples from peoples around the world to find out how closely human beings are related. Their conclusion? All of us are amazingly similar, and traits that determine cultural notions of 'race' — skin color, eye shape — are irrelevant. Now, scientists want to create a U.S.-funded global storehouse of DNA samples before many remote tribes vanish. But critics call the proposed Human Genome Diversity Project 'genetic piracy' and want no part of it.