A racial difference in the prevalence of the Arg506->Gln mutation

Abstract Several recent studies have reported that the factor V Arg506→Gln mutation is present in 3–10% of adults of European descent. To determine if the prevalence is comparable among Blacks, we have initiated a casecontrol study in a large urban hospital in Atlanta which serves a substantial black population. We have evaluated 131 black subjects with confirmed venous or arterial thrombosis and 61 black subjects without a history of thrombosis. Only one case and one control were positive for the Arg506→Gln mutation. We conclude that the mutation is more common among Whites than Blacks.