Caputo Mariela, Amador M A, Santos S, Corach D
Department of Forensic Genetics and DNA Fingerprinting Service, School of Pharmacy and Biochemistry, Universidad de Buenos Aires, Junin 956, 7mo piso, C1113AAD, CABA, Buenos Aires, Argentina.
Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Buenos Aires, Argentina.
Int J Legal Med. 2017 Jan;131(1):107-112. doi: 10.1007/s00414-016-1399-z. Epub 2016 Jun 9.
Polymorphic genetic markers located on the X chromosome might become a complement in particular forensic identification when the biological kinship are deficient. We analyzed forensic statistical parameters of 33 X-chromosome InDel polymorphisms in a sample of 320 individuals from Argentina. The X-chromosome InDel polymorphism (X-InDel) panel was amplified in a single multiplex PCR reaction. Hardy-Weinberg Equilibrium was determined in the female cohort, whereas the male cohort was used to calculate linkage disequilibrium (LD) tested by an extension of Fisher's exact test, D', and Chi-square values. Regarding LD, 15 markers were organized and grouped into six blocks containing two or three linked loci each, namely block I (MID356-MID357), block II (MID448804-MID3703-MID218), block III (MID3705-MID3706-MID304737), block IV (MID197147-MID3754), block V (MID3664-MID284601-MID103547), and block VI (MID3763-MID3728). The haplotype diversity was higher than 0.99 in all cases. Blocks III and VI showed the highest match probability in the studied population, whereas block II showed the lowest. The accumulated power of discrimination was 99.9999991 % in women and 99.9992925 % in men. The mean exclusion chance in trios and duos were 99.9891736 and 99.6099391 %, respectively. Since 15 markers are associated as haplotypic blocks, for a conservative treatment of the data, statistical evaluation should consider their haplotypic frequencies and the remaining 18 markers can be evaluated as independent loci.
当生物亲属关系不足时,位于X染色体上的多态性遗传标记可能成为特殊法医鉴定中的一种补充手段。我们分析了来自阿根廷的320名个体样本中33个X染色体插入缺失多态性的法医统计参数。X染色体插入缺失多态性(X-InDel)面板在单个多重PCR反应中进行扩增。在女性队列中确定了哈迪-温伯格平衡,而男性队列则用于计算通过费舍尔精确检验扩展、D'和卡方值检验的连锁不平衡(LD)。关于LD,15个标记被组织并分组为六个块,每个块包含两个或三个连锁位点,即块I(MID356 - MID357)、块II(MID448804 - MID3703 - MID218)、块III(MID3705 - MID3706 - MID304737)、块IV(MID197147 - MID3754)、块V(MID3664 - MID284601 - MID103547)和块VI(MID3763 - MID3728)。在所有情况下,单倍型多样性均高于0.99。块III和块VI在研究人群中显示出最高的匹配概率,而块II显示出最低的匹配概率。女性的累积鉴别力为99.9999991%,男性为99.9992925%。三联体和二联体中的平均排除机会分别为99.9891736%和99.6099391%。由于15个标记作为单倍型块相关联,为了对数据进行保守处理,统计评估应考虑它们的单倍型频率,其余18个标记可作为独立位点进行评估。