联合应用常染色体STR,X-STR和线粒体SNP鉴别姨甥关系

Combined application of autosomal STR,X-STR and mitochondrial SNP to identify in aunt-nephews relationship

目的基于毛细管电泳技术,联合应用常染色体STR、X-STR及线粒体SNP荧光检测,探讨复杂亲缘关系中姨甥关系的鉴定方法,为复杂亲缘鉴定提供数据和理论依据。方法采用华夏白金、Goldeneye 22NC、Goldeneye 17X、Expressmarker mtDNA-SNP 60荧光检测等试剂盒进行STR和SNP检测,根据分型结果分别采用ITO法、判别函数法和状态一致性评分(identity by state score,IBS)法进行姨甥关系鉴定。结果本案例中通过ITO法计算,姨甥关系指数为8.7324×10^(5),倾向于支持庄某(姨)与李某(外甥女)的姨甥关系;IBS法联合ITO法、判别函数法证实庄某(姨)与庄某某(生母)为全同胞关系,结合庄某某(生母)与李某(外甥女)的累积亲权指数(combined parentage index,CPI)为7.3971×10^(15),证实了庄某(姨)与李某(外甥女)的姨甥关系;线粒体SNP结果表明三者来源于同一母系家族,也支持以上结论。结论对于姨甥等近亲遗传关系,应综合应用多种判定方法进行分析,以获得更为可靠的鉴定意见。

Objective To explore the identification method of aunt-nephew relationship in complex relationship by STR polymorphism detection technique combined with mitochondrial DNA-SNP fluorescence detection,and to provide data and theoretical basis for complex relationship identification.Methods STR and SNP were detected by Huaxia Platinum,Goldeneye 22NC,Goldeneye 17X and Expressmarker MTDNA-SNP 60 fluorescence detection kits.ITO method,discriminant function method and IBS method were used to identify the relationship between aunt and nephew.Results In this case,cumulative avuncular index was 8.7324×10^(5) by ITO method,which tended to support the aunt-niece relationship.IBS method combined with ITO method and discriminant function method proved that aunt and biological mother are full sibling relationship,confirmed that Zhuang(aunt)and Li(niece)is aunt-nephew relationship;The mitochondrial test results showed that the three were from the same maternal family,which also supported this result.Conclusion For the genetic relationship of aunts-nephews and other close relatives,multiple determination methods should be applied to analyze comprehensively to obtain reliable results.