An analysis of mutations at 41 short tandem repeat loci in Han Chinese population / 中国法医学杂志

ABSTRACT

Objective The aim of this study was to investigate mutations of 41 STR loci. Methods 4546 bloodstain samples were typed from 1932 father–mother–child trios by using AGCU_21+1, AGCU_EX22 and GlobalFiler_ExpressTM amplification Kit. Calculate the mutation rates of STR loci. Results 154 mutations were identified at 32 of the 41 loci. The average mutation rate was 1.0×10-3per locus(95%CI: 0.8~1.1×10-3), and the mutations of SE33 was highest. 152(98.7%) mutation events were one-step mutation, 2(1.3%) events were two-steps. The mutation events occurred in 150 father–mother–child triplets. The mutations in 146(97.3%) triplets occurred at single locus, 8 mutations were observed at two loci in 4(2.7%) triplets simultaneously. 104 paternal and 22 maternal mutations could be determined under 79212 paternal and maternal allelictransfers. The ratio of paternal versus maternal mutations was 4.7:1, and 28 unassigned mutations were observed. Conclusion STR mutation are common in paternity testing, and we should pay more attention to it.