Chromosome mapping of Y chromosomal STR DYS385 loci

我们开发了一种Y染色体连锁同源DYS385基因座的基因分型方法，结合基因座特异的聚合酶链式反应和先前报道的方法。重复的DYS385a(5‘端)和DYS385b(3’端)基因座位于Y染色体上，相距约41kbp，且相互颠倒，该数据来源于NCBI中的人类基因组序列，在每个基因座的上下424bp处存在序列差异。使用针对该基因间隔区设计的引物进行座位特异性扩增，产生约900bp的片段。聚合酶链式反应产物中的多态四核苷酸阵列根据先前报道的程序进行分型。用这种方法对20名男性受试者进行了基因分型。DYS385a基因座有(GAAA)_13~(GAAA)_21等位基因，DYS385b基因座有(GAAA)_9~(GAAA)_15等位基因。在同一个体中，除相同排列外，DYS385a等位基因均大于DYS385b等位基因。这些数据表明，DYS385a和DYS385b基因座完全可以被扩增出来用于区分，等位基因的基因分型为法医学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.