Chromosome mapping of Y chromosomal STR DYS385 loci

我们开发了一种Y染色体连锁同源DYS385位点的基因分型方法，结合位点特异性PCR扩增和先前报道的方法。重复的DYS385a（5’端）和DYS385b(3’？从NCBI的人类基因组序列中获得的数据显示，在Y染色体上，每个基因座的上游和下游分别有424bp的序列差异。利用为该基因间区设计的引物进行基因座特异性扩增，得到了长度约900 bp的片段。PCR产物中的多态四核苷酸序列按照先前报道的程序进行分型。用该方法对20名男性受试者进行基因分型。在DYS385a位点上观察到等位基因（GAAA）_13 ~ (GAAA)_21，在DYS385b位点上观察到等位基因（GAAA）_9 ~ (GAAA)_15。DYS385a等位基因（除相同序列外）在同一受试者中均大于DYS385b等位基因。这些数据表明，DYS385a和DYS385b基因座可以完全扩增以进行区分，并且等位基因的基因型为法医案件工作和群体遗传学提供了有用的信息。

We developed a method for genotyping Y chromosome-linked homologous DYS385 loci individually, combining locus-specific PCR amplification and previously reported procedures. Duplicated DYS385a (5' -end) and DYS385b (3' ?end) loci were located about 41K bp apart and inverted to each other in the Y chromosome, which data was obtained from the human genome sequence in NCBI, and sequence differences were found at 424 bp down- and upstream of each locus. The locus-specific amplifications were performed using primers designed for this intergenic region, and fragments about 900 bp in length were produced. Polymorphic tetranucleotide arrays in the PCR products were typed according to procedures reported previously. Twenty male subjects were genotyped using this method. Alleles (GAAA)_13 to (GAAA)_21 were observed at the DYS385a locus, and those at DYS385b included alleles (GAAA)_9 to (GAAA)_15. DYS385a alleles, excluding those of identical arrays, were always larger than DYS385b alleles in the same subjects. These data suggest that the DYS385a and DYS385b loci can be amplified completely for discrimination, and the genotypes of the alleles provide information useful for forensic case work and population genetics.