中国汉族人群41个STR基因座突变情况的观察分析

目的调查41个STR基因座在中国汉族人群中的突变情况。方法收集1 932个三联体家系4 546份血样本,采用AGCU_21+1、AGCU_EX22、Global Filer_Express~(TM)系统扩增41个STR基因座分型,统计各基因座发生突变的频率。结果 150个三联体在32个基因座共观察到154次突变,平均突变率为1.0×10~(-3)(95%CI:0.8~1.1×10~(-3)),突变率最高的是基因座SE33。其中一步突变152次(98.7%),两步突变2次(1.3%);146个三联体仅1个基因座发生突变(97.3%),4个三联体在2个基因座发生突变(2.7%);父、母来源突变比率约为4.7:1。结论 STR基因座等位基因突变现象较为常见,亲子鉴定时应引起注意。

An analysis of mutations at 41 short tandem repeat loci in Han Chinese population

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.