26 NEW POLYMORPHIC MICROSATELLITE MARKERS AROUND THE HLA-B, HLA-C ANDHLA-E LOCI IN THE HUMAN MHC CLASS-I REGION

The human major histocompatibility complex (MHC) class I region is bel ieved to contain a large number of disease-related loci for diseases s uch as Behcet's disease and psoriasis vulgaris. Although many novel ge nes have recently been identified in this region, it still appears to be difficult to relate any of these new genes to MHC class I-associate d diseases as causative genetic factors. During the course of large-sc ale genomic sequencing of the human MHC class I region, we identified 262 microsatellite sequences with dinucleotide to pentanucleotide repe ats around the HLA-B, -C and HLA-E genes. Of these, 26 microsatellites were investigated for repeat polymorphism using 60 HLA homozygous B-c ell lines and 60 healthy random individuals The average number of alle les at these microsatellite loci was 9.6 with a PIC (polymorphism cont ent value) of 0.69. These new polymorphic microsatellite markers will probably be very useful for precise mapping of disease-related genes w ithin the HLA class I region in linkage analysis Moreover, they will p rovide a powerful tool to study recombination events in this region, w hich contributes to haplotypic diversification.