Iacovacci Giuseppe, D'Atanasio Eugenia, Marini Ornella, Coppa Alfredo, Sellitto Daniele, Trombetta Beniamino, Berti Andrea, Cruciani Fulvio
Carabinieri, Reparto Investigazioni Scientifiche di Roma, Sezione di Biologia, Rome, Italy.
Dipartimento di Biologia e Biotecnologie "Charles Darwin", Sapienza Università di Roma, Rome, Italy.
Forensic Sci Int Genet. 2017 Mar;27:123-131. doi: 10.1016/j.fsigen.2016.12.015. Epub 2016 Dec 29.
By using the recently introduced 6-dye Yfiler Plus multiplex, we analyzed 462 males belonging to 20 ethnic groups from four eastern African countries (Eritrea, Ethiopia, Djibouti and Kenya). Through a Y-STR sequence analysis, combined with 62 SNP-based haplogroup information, we were able to classify observed microvariant alleles at four Y-STR loci as either monophyletic (DYF387S1 and DYS458) or recurrent (DYS449 and DYS627). We found evidence of non-allelic gene conversion among paralogous STRs of the two-copy locus DYF387S1. Twenty-two diallelic and triallelic patterns observed at 13 different loci were found to be significantly over-represented (p<10) among profiles obtained from cell lines compared to those from blood and saliva. Most of the diallelic/triallelic patterns from cell lines involved recurrent mutations at rapidly mutating loci (RM Y-STRs) included in the multiplex (p<10). At haplotype level, intra-population diversity indices were found to be among the lowest so far reported for the Yfiler Plus, while statistically significant differences among countries and ethnic groups were detected when considering haplotype frequencies alone (F) or by using molecular distances among haplotypes (Φ). The strong population subdivision observed is probably the consequence of the patrilineal social organization of most eastern African ethnic groups, and suggests caution in the use of country-based haplotype frequency distributions for forensic inferences in this region.
通过使用最近推出的6染料Yfiler Plus复合扩增系统，我们分析了来自东非四个国家（厄立特里亚、埃塞俄比亚、吉布提和肯尼亚）20个民族的462名男性。通过Y-STR序列分析，并结合62个基于SNP的单倍群信息，我们能够将在四个Y-STR位点观察到的微变异等位基因分类为单系（DYF387S1和DYS458）或重复出现（DYS449和DYS627）。我们发现了两拷贝基因座DYF387S1的旁系同源STR之间存在非等位基因转换的证据。与从血液和唾液中获得的图谱相比，在13个不同位点观察到的22种双等位基因和三等位基因模式在细胞系获得的图谱中显著过度呈现（p<10）。细胞系中的大多数双等位基因/三等位基因模式涉及复合扩增系统中包含的快速突变位点（RM Y-STR）的重复突变（p<10）。在单倍型水平上，发现群体内多样性指数是Yfiler Plus迄今为止报道的最低水平之一，而仅考虑单倍型频率（F）或使用单倍型之间的分子距离（Φ）时，在国家和民族之间检测到统计学上的显著差异。观察到的强烈群体细分可能是大多数东非民族父系社会组织的结果，并表明在该地区使用基于国家的单倍型频率分布进行法医推断时要谨慎。
