Haplotypic polymorphisms and mutation rate estimates of 22 Y-chromosome STRs in the Northern Chinese Han father–son pairs

Y chromosome Short tandem repeats (Y-STRs) analysis has been widely used in forensic identification, kinship testing, and population evolution. An accurate understanding of haplotype and mutation rate will benefit these applications. In this work, we analyzed 1123 male samples from Northern Chinese Han population which including 578 DNA-confirmed father-son pairs at 22 Y-STRs loci. A total of 537 haplotypes were observed and the overall haplotype diversity was calculated as 1.0000 ± 0.0001. Except that only two haplotypes were observed twice, all the rest of the 535 were unique. Furthermore, totally 47 mutations were observed during 13,872 paternal meiosis. The mutation rate for each locus estimates ranged from 0.0 to 15.6 × 10(−3) with an average mutation rate 3.4 × 10(−3) (95% CI 2.5–4.5 × 10(−3)). Among the 22 loci, DYS449, DYS389 II and DYS458 are the most prone to mutations. This study adds to the growing data on Y-STR haplotype diversity and mutation rates and could be very useful for population and forensic genetics.