CCR5-Delta32 allele frequencies in Ashkenazi Jews.

This study was carried out to determine the 32-bp deletion allele frequencies in the CCR5 gene (CCR5-Delta32) in various populations of Jews of eastern European origin (Ashkenazi Jews). The total population sample (n = 351) represented Ashkenazi Jews originating from seven geographic groups in Europe. The overall frequency of the CCR5-Delta32 allele was elevated (13.7%), although some important differences in frequencies occurred among the seven countries included in the survey; the frequency was highest (25.9%) in those of Lithuanian origin. There is an apparent trend (r = 0.74) involving a lowering of the Delta32 allele frequencies moving from north to south in the seven populations tested. The Delta32 frequencies obtained were compared to those already published for non-Jewish populations inhabiting the same countries and the differences in frequencies were not significant, with the exception of Lithuania (chi(2) = 2.20, p < 0.03). Founder effect and genetic drift are proposed to explain the elevated values observed in Ashkenazi Jews and those originating from Lithuania.