Scientists at Georgetown University have discovered some disturbing news for African-Americans. They are more likely than other groups to develop life-threatening clots after receiving a drug-coated stent, and researchers are not sure why. Even after taking into account other known risk factors like diabetes, hypertension, and kidney problems, they found that African-Americans still experience a higher rate of thrombosis or clotting. Ron Waksman, lead author of the study--which appears in Circulation: Journal of the American Heart Association--is urging more studies into the genetic differences that could cause this problem. "The bottom line is this is not just because this population is sicker or less compliant, but there is something else there that needs to be explored," Waksman says in a statement. American Heart Association release