KCNQ1内含子1a中STR基因座遗传多态性及PIA分型

The genetic polymorphism and parentally imprinted allele typing at a STR locus in intron 1a of imprinted gene KCNQ1

目的调查汉族群体KCNQ1基因内含子1a中STR基因座的遗传多态性,并采用PIA分型技术确定等位基因的亲代来源。方法用PCR-STR分型技术对230例武汉汉族无关个体样本进行KCNQ1基因内含子1a中STR基因座分型检测;同时选用两种甲基化敏感的限制酶(msRE)HhaⅠ和HpaⅡ对家系中孩子的基因组DNA进行消化后,采用PIA分型技术检测父源等位基因。结果KCNQ1内含子1a中STR基因座在汉族人群中检出10个等位基因、24种基因型,其个体识别能力(PD)、多态性信息含量(PIC)和非父排除率(PE)分别为0.852、0.66和0.484。HhaⅠ和HpaⅡ可消化个体的母源等位基因,PIA分型仅能检测出单一的父源等位基因。结论KCNQ1内含子1a中STR基因座在汉族群体具有较高的遗传多态性,PIA分型技术可以确定个体等位基因的亲代来源,具有较高的法医学应用价值。

Objective To investigate the genetic polymorphism of a STR locus in intron la of imprinted gene KCNQ1, and determine the parental origin of alleles using parentally imprinted allele （PIA） typing technique. Methods 230 unrelated individuals of Han population in Wuhan area were analyzed by PCR-STR typing technique, and the paternal allele for this locus was detected selectively by PIA typing technique with the methylation-sensitive restriction enzymes （msREs） HhaIand HpaⅡ. Results 10 alleles and 24 genotypes were observed for the STR locus in intron la of KCNQI gene in Chinese Han population in Wuhan, and the power of discrimination （PD）, polymorphism information content （PIC） and probability of paternity exclusion （PE） were 0. 852, 0.66 and 0. 484 respectively. The msREs, HhaIand HpaⅡ, could digest the maternal allele, and only a single band derived from the paternal allele was detected by PIA typing technique. Conclusion This locus is highly polymorphic. The parental origins of alleles in an individual can be determined by PIA typing, and this technique can be used in forensic science as a valuable tool.