Estimating African American Admixture Proportions by Use of Population- Specific Alleles

Orleans; and Houston) and in Jamaica, using nine au-tosomal DNA markers. These markers either are pop-ulation-specific or show frequency differences 145 % be-tween the parental populations and are thus especially informative for admixture. European genetic ancestry ranged from 6.8 % (Jamaica) to 22.5 % (New Orleans). The unique utility of these markers is reflected in the low variance associated with these admixture estimates (SEM 1.3%–2.7%). We also estimated the male and fe-male European contribution to African Americans, on the basis of informative mtDNA (haplogroups H and L) and Y Alu polymorphic markers. Results indicate a sex-biased gene flow from Europeans, the male contribution being substantially greater than the female contribution. mtDNA haplogroups analysis shows no evidence of