SELECTIVE COEVOLUTION OF THE D6STNFA MICROSATELLITE REGION WITH HLA CLASS-I AND CLASS-II LOCI

We analyzed the HLA-A, -B, -DR and -DQ phenotypes and 12 microsatellit e locus genotypes within and close to the major histocompatibility com plex in a panel of 98 randomly selected, healthy, unrelated Dutch Cauc asoid individuals. Allele frequencies and Hardy-Weinberg equilibrium ( HWE) were calculated. Also, the linkage disequilibrium patterns betwee n HLA and microsatellite loci were studied. The HLA-A, -B, -DR, -DQ an d six microsatellite loci centromeric of the HLA-A showed HWE. In cont rast, all microsatellites telomeric of the HLA-A showed deviation from HWE due to excess of homozygosity. Linkage disequilibrium analyses pr ovided strong evidence that among the tested microsatellite loci only the alleles of the D6STNFa locus are in linkage disequilibrium with bo th HLA-B and -DR. Our results suggest that selection acting on the HLA genes includes the D6STNFa locus and linked genes.