中国汉族人群四个STR的多态性及其与IDDM的相关性研究

Polymorphisms of four STRs and their associations with IDDM in Chinese Han population

目的 获得 D15 S6 5 7、D11S136 9、D6 S2 42 0、D6 S5 0 3位点在中国成都汉族人群中的群体遗传数据 ,并研究上述 4种短串联重复序列 (short tandem repeats,STR)的多态性与胰岛素依赖型糖尿病(insulin- dependent diabetes mellitus,IDDM)的关系。方法 应用 PCR- polyacrylamide gel electrophoresis(PAGE)结合产物直接测序的技术 ,对 10 5名无亲缘关系的成都地区正常汉族人和 48例 IDDM患者的上述 4种 STR的多态性进行分析。结果 D15 S6 5 7位点发现 7种等位基因 ,D11S136 9位点发现 5种等位基因 ,D6 S2 42 0位点发现 7种等位基因 ,D6 S5 0 3位点发现 4种等位基因 ;4个 STR位点的基因型分布均符合Hardy- Weinberg平衡 ,杂合度分别为 0 .75 2 4、0 .6 0 0 0、0 .6 2 86、0 .6 5 71,多态信息量分别为 0 .76 16、0 .44 30、0 .5 345、0 .5 932。在 IDDM组中 ,D15 S6 5 7的等位基因 A5 ,D11S136 9的等位基因 A5 和 D6 S2 42 0的等位基因 A4的频率显著高于正常对照组 (P值校正值均小于 0 .0 5 )。结论 4个 STR均适合作为疾病关联分析、法医学鉴定和人类遗传学研究的遗传标记 ;中国汉族人群中 D15 S6 5 7、D11S136 9、D6 S2 42 0的多态性与IDDM相关。

Objective To obtain the polymorphic data of short tandem repeat(STR) loci of D15S657, D11S1369, D6S2420 and D6S503 in Chinese Han population and to study the association of these four STR loci with insulin dependent diabetes mellitus(IDDM). Methods The polymorphisms of the four STRs were studied by polymerase chain reaction polyacrylamide gel electrophoresis(PCR PAGE) followed by direct sequencing of PCR products in 105 normal Chinese Hans and 48 patients with IDDM. Results Seven alleles at D15S657 locus, 5 alleles at D11S1369 locus, 7 alleles at D6S2420 locus and 4 alleles at D6S503 locus were found. No deviation from Hardy Weinberg equilibrium was observed. The heterozygosities of these loci were 0.7524, 0.6000, 0.6286, 0.6571 and the polymorphic information contents(PIC) 0.7616, 0.4430, 0.5345 and 0.5932, respectively. The allele frequencies of allele A 5 at D15S657 locus, allele A 5 at D11S1369 locus and allele A 4 at D6S2420 locus were increased significantly in patients with IDDM, compared to those in the control group. Conclusion The four STRs, used as genetic markers, were suitable for case control study, forensic medicine identification and population genetic study. There is an association between the polymorphisms of D15S657, D11S1369, D6S2420 and IDDM.