硒蛋白P基因多态性与结直肠癌遗传易感性的关联性分析

目的:探讨硒蛋白P(Sepp1)基因rs7579位点单核苷酸多态性(SNPs)与结直肠癌遗传易感性的关系,为结直肠癌的遗传学机制研究提供理论依据。方法:采用病例对照研究方法,采用四引物扩增阻碍突变体系聚合酶链反应(tetra-primer ARMS-PCR)技术检测130例结直肠癌患者及153名体检健康者Sepp1基因rs7579位点基因型和等位基因频数,并经测序验证。分析Sepp1基因rs7579位点基因型、等位基因与结直肠癌遗传易感性的关联性,并分析不同临床特征结直肠癌患者Sepp1基因rs7579位点基因型与结直肠癌遗传易感性的关联性。结果:结直肠癌组和健康对照组研究对象Sepp1基因 rs7579 位点多态性分布情况均符合Hardy-Weinberg平衡(P>0.05),结直肠癌组患者和健康对照者Sepp1基因rs7579位点GG、GA和AA基因型频数及G、A等位基因频数比较差异无统计学意义(P>0.05)。分层分析,年龄≥55岁组中,结直肠癌组和健康对照者组研究对象rs7579位点GG、GA和AA基因型频数比较差异有统计学意义(χ²=3.228,P=0.050),结直肠癌组患者AA基因型频率明显低于健康对照组(χ²=3.228,P=0.050,OR=0.566,95%CI:0.320-0.999)。结论:Sepp1基因rs7579位点多态性与结直肠癌的发病无关联,A等位基因可能是55岁以上中国人群降低结直肠癌发病的保护性因素之一。

Analysis on correlation between genetic susceptibility of colorectal cancer and polymorphisms of selenoprotein P

Objective To investigate the correlation between the polymorphisms of rs7579 site at selenoprotein P(Sepp1) gene and the genetic susceptibility of colorectal cancer,and to provide the theoretical basis for studying the genetic mechanism of colorectal cancer. Methods A case-control study was used in this research.The genotypic and allelic frequencies of Sepp1 gene were detected both in 130 patients with colorectal cancer and 153 healthy people by tetra-primer amplification refractory mutation system-polymerase chain reaction(tetra-primer ARMS-PCR)method,which was confirmed by gene sequencing analysis.The association between genotypic and allelic frequencies of rs7579 site at Sepp1 gene and genetic susceptibility of colorectal cancer was analyzed,then the association between the genotypes of rs7579 site at Sepp1 gene and genetic susceptibility of colorectal cancer in the patients with colorectal cancer with different clinical features was also analyzed. Results The distribution of polymorphism of rs7579 site at Sepp1 gene did not deviate from Hardy-Weinberg equilibrium in both case and control groups(P>0.05).There were no significant differences of the genotypic and allelic frequencies of rs7579 site at Sepp1 gene site between case group and control group(P>0.05).The stratification analysis results showed that there was significant difference of the genotypic frequency of rs7579 site between case group and control group in the patients more than 55 years old(χ²=3.228,P=0.050),and the genotypic frequency of AA of the patients in case group was significantly lower than that in control group(χ²=3.228,P=0.050,OR=0.566,95%CI:0.320-0.999). Conclusion The polymorphism of rs7579 site at Sepp1 gene is irrelevant to the pathogeny of colorectal cancer.Allele A may be one of the protective factors that reduce the morbidity of colorectal cancer among Chinese people older than 55 years old.