Li Fayuan, Zhao Peng, Xiao Cheng, Feng Chunlei, Chen Ling, Du Weian
AGCU ScienTech Incorporation, Wuxi 214174, China.
School of Forensic Medicine, Southern Medical University, Guangzhou 510515, China.
Leg Med (Tokyo). 2019 Mar;37:41-44. doi: 10.1016/j.legalmed.2019.01.003. Epub 2019 Jan 2.
Y chromosome short tandem repeats (Y-STRs) are widely used in forensic DNA analysis. Y-STRs usually genotyped as a monoallelic pattern, or a diallelic pattern at some double-copy loci. Abnormal genotypes with three or four alleles have been reported at DYS385a/b, which is a double-copy locus. However, multi-allelic patterns with more than four alleles have not been reported at this locus. In this study, abnormal five-allelic patterns at DYS385a/b locus were observed in 2 out of 7760 unrelated males from Henan Province, detected by the HG19+14Y fluorescence detection kit; and abnormal six-allelic pattern was observed in 1 out of 4920 unrelated males from Guangdong Province, detected by the AGCU Data Y30 fluorescence kit. The genotypes of these abnormal samples were confirmed again by the Yfiler® Plus and PowerPlex® Y23 kits. In order to understand the genomic structure of the extra alleles at this locus, forward and reverse primers were designed to sequence the three samples. The results showed that the five-banded and six-banded pattern genotype did exist at DYS385a/b locus. These data enriched the knowledge about multi-allelic patterns at DYS385a/b locus, which allowed the use of DYS385a/b profile in forensic analysis, even with multi-allelic patterns.
Y染色体短串联重复序列（Y-STRs）广泛应用于法医DNA分析。Y-STRs通常以单等位基因模式进行基因分型，或在一些双拷贝基因座处以双等位基因模式进行基因分型。在双拷贝基因座DYS385a/b处已报道了具有三个或四个等位基因的异常基因型。然而，该基因座尚未报道有超过四个等位基因的多等位基因模式。在本研究中，使用HG19 + 14Y荧光检测试剂盒在来自河南省的7760名无关男性中的2名中观察到DYS385a/b基因座处的异常五等位基因模式；使用AGCU Data Y30荧光试剂盒在来自广东省的4920名无关男性中的1名中观察到异常六等位基因模式。这些异常样本的基因型通过Yfiler® Plus和PowerPlex® Y23试剂盒再次得到确认。为了了解该基因座额外等位基因的基因组结构，设计了正向和反向引物对这三个样本进行测序。结果表明，DYS385a/b基因座确实存在五带型和六带型模式基因型。这些数据丰富了关于DYS385a/b基因座多等位基因模式的知识，使得即使存在多等位基因模式，DYS385a/b图谱也可用于法医分析。
