Ma Yan, Kuang Jin-Zhi, Zhu Wei, Yang Zhi, Wang Yu-Jian, Nie Tong-Gang, Li Chen, Hou Yi-Ping
Department of Forensic Biology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, 610041 Sichuan, China.
J Forensic Sci. 2012 Nov;57(6):1630-3. doi: 10.1111/j.1556-4029.2012.02145.x. Epub 2012 Apr 17.
The male-specific Y-chromosomal short tandem repeat (STR) is a useful tool in forensic casework. The Y haplotype comprised of 16 loci, which is amplified simultaneously by AmpFlSTR(®) Yfiler(TM) PCR kit and provides strong exculpatory evidence in individual identification. We reported a rare Y-STR profile with a null allele at the DYS448 locus and an off-ladder allele at the DYS456 locus, when genotyping material from a vaginal swab in an alleged rape case. Sequence analysis revealed that the DYS448 null allele was a true type of null allele because of a total deletion of 11 upstream repeats and 9bp of the N(42) region, and there were numerous primer binding site mutations as well. The amplicon of the DYS456 locus was a small 92-bp fragment that was off-ladder, and sequencing analysis showed that there were only 10 repeats (AGAT)(10). This Y chromosome haplotype that was comprised of two variations provided helpful evidence for personal identification.
男性特有的Y染色体短串联重复序列（STR）是法医案件工作中的一种有用工具。由16个位点组成的Y单倍型，可通过AmpFlSTR(®) Yfiler(TM) PCR试剂盒同时扩增，并在个体识别中提供有力的无罪证据。在对一起涉嫌强奸案的阴道拭子样本进行基因分型时，我们报告了一种罕见的Y-STR图谱，其中DYS448位点存在无效等位基因，DYS456位点存在非标准等位基因。序列分析表明，DYS448无效等位基因是真正的无效等位基因类型，因为其上游11个重复序列和N(42)区域的9个碱基对完全缺失，并且还存在许多引物结合位点突变。DYS456位点的扩增子是一个92个碱基对的小片段，为非标准片段，测序分析表明其只有10个重复序列（AGAT）(10)。这种由两种变异组成的Y染色体单倍型为个人识别提供了有用的证据。
