Muñiz-Mendoza R, Ayala-Madrigal M L, Partida-Pérez M, Peregrina-Sandoval J, Leal-Ugarte E, Macías-Gómez N, Peralta-Leal V, Meza-Espinoza J P, Moreno-Ortiz J M, Ramírez-Ramírez R, Suárez-Villanueva S, Gutiérrez-Angulo M
Instituto de Genética Humana, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Jalisco, Mexico.
Genet Mol Res. 2012 Aug 13;11(3):2315-20. doi: 10.4238/2012.June.27.6.
DNA repair proteins maintain DNA integrity; polymorphisms in genes coding for these proteins can increase susceptibility to colorectal cancer (CRC) development. We analyzed a possible association of MLH1 -93G>A and 655A>G and XRCC1 Arg194Trp and Arg399Gln polymorphisms with CRC in Mexican patients. Genomic DNA samples were obtained from peripheral blood of 108 individuals with CRC (study group) at diagnosis and 120 blood donors (control group) from Western Mexico; both groups were mestizos. The polymorphisms were detected by PCR-RFLP. Association was estimated by calculating the odds ratio (OR). We found that the MLH1 and XRCC1 polymorphisms were in Hardy- Weinberg equilibrium. The MLH1 655A>G polymorphism in the 655G allele was associated with a 2-fold increase risk for CRC (OR = 2.04 and 95% confidence interval (95%CI) = 1.12-3.69; P < 0.01), while the MLH1 -93G>A polymorphism allele was associated with a protective effect (OR = 0.60, 95%CI = 0.40-0.89; P = 0.01 in the -93A allele and OR = 0.32, 95%CI = 0.13-0.79; P = 0.01 in the AA genotype). The XRCC1 Arg194Trp and Arg399Gln polymorphisms did not show any significant associations. In conclusion, we found that MLH1 -93G>A and 655A>G polymorphisms are associated with CRC in Mexican patients.
DNA修复蛋白维持DNA的完整性；编码这些蛋白的基因中的多态性可增加患结直肠癌（CRC）的易感性。我们分析了墨西哥患者中MLH1 -93G>A和655A>G以及XRCC1 Arg194Trp和Arg399Gln多态性与CRC之间的可能关联。基因组DNA样本取自108例诊断为CRC的个体（研究组）的外周血以及来自墨西哥西部的120名献血者（对照组）；两组均为混血儿。通过PCR-RFLP检测多态性。通过计算比值比（OR）评估关联性。我们发现MLH1和XRCC1多态性处于哈迪-温伯格平衡。MLH1 655A>G多态性中的655G等位基因与CRC风险增加2倍相关（OR = 2.04，95%置信区间（95%CI）= 1.12 - 3.69；P < 0.01），而MLH1 -93G>A多态性等位基因具有保护作用（-93A等位基因的OR = 0.60，95%CI = 0.40 - 0.89；P = 0.01，AA基因型的OR = 0.32，95%CI = 0.13 - 0.79；P = 0.01）。XRCC1 Arg194Trp和Arg399Gln多态性未显示出任何显著关联。总之，我们发现MLH1 -93G>A和655A>G多态性与墨西哥患者的CRC相关。
