Complex divergence at a microsatellite marker C1_2_5 in the lineage of HLA-Cw/-B haplotype

The human leukocyte antigen (HLA) complex locus has shaped a framework for evolutionary processes because of the dense clustering and strong linkage disequilibrium (LD) of polymorphic genes. Although the landscape of LD among conventional single-nucleotide polymorphisms (SNPs) has been described, the data on the lineage of major histocompatibility complex (MHC) haplotype are limited to pairwise comparisons of several haplotypes in Caucasoid populations. Multi-allelic markers, including microsatellite markers, may provide us with a larger power to analyze the MHC haplotype lineage because the mutation rate of microsatellite exceeds that of SNPs by several orders of magnitude. In this study, we investigated the complex structure of repeat motifs in a microsatellite to figure out the structural lineage of HLA-Cw/-B segments in Japanese. It was found that the genetic differences of HLA-Cw/-B haplotype lineage were reflected by repeat motif patterns at C1_2_5 locus, suggesting that unique mutational dynamics of microsatellites may be a useful marker to chase the haplotype lineage. Journal of Human Genetics (2009) 54, 224-229; doi: 10.1038/jhg.2009.15; published online 27 February 2009