Evidence for recent selection of the CCR5-delta 32 deletion from differences in its frequency between Ashkenazi and Sephardi Jews.
Recent studies have shown higher frequencies of the CCR5-delta 32 allele and the CCR5-delta 32/delta 32 genotype, which confers protection against HIV infection, in northern Europe as compared to Mediterranean countries. Here, we analyse the prevalence of CCR5-delta 32 in 922 HIV seronegative blood donors in Israel to verify its frequency in Jews of Ashkenazi and Sephardi origin. A significant difference (P < 0.001) was found between the CCR5-delta 32 allele frequency in Ashkenazi (13.8%) vs (4.9%) Jews. In contrast, no significant difference was observed in the frequency of the CCR2-641 mutation between Ashkenazi (9.2%) and Sephardi (13.4%) Jews. Using the Island model we calculate that a minimal genetic migration rate of 3% per generation would have been necessary if the higher CCR5-delta 32 prevalence in Ashkenazi is to be fully explained by mixing with the indigenous north-European populations. This putative migration rate is 20-fold higher than that currently estimated from other genes, and would correspond to a non-realistic minimal current admixture of 80%. Thus, our results suggest that a positive selection process for CCR5-delta 32 should have occurred in northern Europe at most a 1000 years ago, after the Ashkenazi Jews separated from their Sephardi kin and moved to north Europe.
Maayan
S
S
Hadassah Hospital, Jerusalem 91000, Israel.
Zhang
L
L
Shinar
E
E
Ho
J
J
He
T
T
Manni
N
N
Kostrikis
L G
LG
Neumann
A U
AU
D000483:Alleles; D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D005060:Europe / Q000208:ethnology; D005787:Gene Frequency; D005838:Genotype; D015658:HIV Infections / Q000235:genetics; D006801:Humans; D007557:Israel; D007585:Jews / Q000235:genetics*; D019083:Mediterranean Region / Q000208:ethnology; D019713:Receptors, CCR5 / Q000235:genetics*; D012641:Selection, Genetic; D017384:Sequence Deletion
D017931:DNA Primers; D019713:Receptors, CCR5