Y-STR单倍型在大家系中的差异研究

Variation of Y-STR Haplotype in a Deep-rooted Pedigree

目的研究三种不同的Y-STR分型体系(Yfiler,Yfiler~?Plus和快速突变Y-STRs)在家系遗传过程中所展现出的变异程度。方法选取一遗传关系清晰的汉族家系,利用Yfiler~?Plus复合扩增系统和包含7个快速突变Y-STR基因座的复合扩增系统,得到所采男性样本32个Y-STR基因座的分型数据,统计分析Y-STR单倍型在世代遗传中的变化程度。结果同一家系不同男性个体的Y-STR单倍型具有一定的多样性,并且与Y-STR单倍型包含的基因座数量和基因座突变率有关;当家系中两名男性个体相隔10次减数分裂时,其Yfiler单倍型不一致的概率为7.35%,Yfiler Plus单倍型不一致的概率是91.2%,快速突变Y-STR单倍型不一致的概率则为100%。结论包含不同Y-STR基因座组合的Y-STR单倍型在世代遗传过程中的变化程度差异较大,在亲权鉴定和家系排查过程中特别是当Y-STR分型体系包含快速突变Y-STR基因座时应留心关注。本研究对Y-STR数据库建设中的采样规则和基因座选择也有参考价值。

Objective To investigate the Y-STR haplotype variations within a pedigree by three Y-STR tests(Y filer,Y filer?Plus and the rapidly mutating Y-STR).Methods 32 Y-STR genotypes were obtained with both the Y filer?Plus kit and another multiplex amplification system enclosing 7 rapidly mutating Y-STRs to demonstrate the variations of Y-STR haplotypes.The variation patterns were analyzed through their emergence among generation descending.Results For different males in the big pedigree tested,their Y-STR haplotypes are of certain diversity,showing them very closely related to the amount and mutation rates of the involving Y-STR loci.The proportion of different Y-STR haplotypes increases along with meiosis times between individuals.When two relative males were separated by 10 meioses,the percentage of their Y-STR haplotypes was differentiated to 7.35%by Y filer,91.2%by Y filer?Plus,and even 100%by rapidly mutating Y-STR.Conclusions Y-STR haplotypes,when consisted of different sets of Y-STR loci,reveal bigger diversity among various individuals due to the diverse mutating speed across their generation descending.Therefore,more attention should be paid in paternity test and familial search,especially when the Y-STR haplotype contains rapidly mutating Y-STRs.The discovery here should also be suggestive for Y-STR database construction.