Mutation rate varies among alleles at a microsatellite locus: Phylogenetic evidence

摘要: The understanding of the mutational mechanism that generates high levels variation at microsatellite loci lags far behind the application these genetic markers. A phylogenetic approach was developed to study pattern and rate mutations a dinucleotide locus tightly linked HLA-DQB1 (DQCAR). random Japanese population ( n = 129) collection of multiethnic samples 941) were typed DQB1 DQCAR loci. phylogeny DQB1 alleles was then reconstructed superimposed onto phylogeny. This approach allowed us group share common ancestor. The results indicated mutation varies drastically among within this single locus. Some alleles never mutated during long period evolutionary time. Sequencing representative showed lost their ability mutate because nucleotide substitutions shorten length uninterrupted CA repeat arrays; in contrast, all mutating had relatively longer perfect sequences.