【摘要】 目的 :　探讨中国人iNOS基因是否存在单核苷酸多态性及其在中国人中的频率。方法 :DHPLC方法结合直接测序和PCR RFLP技术 ,在有代表性的中国人中进行筛查。结果 :在iNOS基因全部被测外显子中 ,有 6个外显子发现可疑双峰图型 ,可能存在杂合突变 ,对其测序后在iNOS基因第 16外显子发现C→T突变 (称为Tsp多态性 ) ,使编码的氨基酸由丝氨酸 (serine,Ser)改变为亮氨酸 (leucine ,Leu) ,设计PCR RFLP方法并监测全部测序样本 ,PCR RFLP与测序结果一致。在有代表性的 43例中国人中 ,Ser和Leu等位基因频率分别为 75 .5 8% (6 5 / 86 )和 2 4.42 % (2 1/ 86 ) ;三种基因型观察频率分别为Ser/Ser :6 2 .79% ;Ser/Leu :2 5 .5 8% ;Leu/Leu :11.6 3% ,与期望频率 (分别为 5 7.12 % ,36 .91%和 5 .96 % )差异无显著性 (P >0 .0 5 ) ,说明符合Hardy Weinberg遗传平衡定律。 结论 :中国人群中存在iNOS基因Tsp多态性 ,且频率较高更多还原

【Abstract】 Objective:To detect the single nucleotide polymorphisms (SNPs) in iNOS gene, and its frequency in Chinese population.Methods: Denaturing high performance liquid chromatography (DHPLC) combined with direct sequence and PCR RFLP techniques were used in representative Chinese population.Results:Among all detected exons of iNOS gene, six exons were found to show possible heteroduplex double peaks, which meant possible heteroduplex samples. Sequencing was conducted among the possible samples, and only exon 16 was found to have a heterozygous C→T mutation (called Tsp polymorphiam), which changed the coding amino acid from serine (TCG) to leucine (TTG). PCR RFLP method was designed to re identify the result of sequencing. Results indicated that all sequencing identified heterozygous samples were also detected to be heterozygous using PCR RFLP method. The allele frequencies for Ser and Leu were 75.58% (65/86) and 24.42% (21/86) respectively among the 43 Chinese individuals. The observed frequencies of three genotypes in the same population (Ser/Ser, 62.79%; Ser/Leu, 25.58%; and Leu/Leu, 11.63%) were not different from those expected from the Hardy Weinberg equilibrium (57.12%, 36.91% and 5.96%, respectively; P >0.05); indicating that they accord with Hardy Weinberg equilibrium law. Conclusion: Tsp polymorphism exists in Chinese population, and has a higher frequency.更多还原