[Mismatch repair gene hMLH1 A655G/A polymorphism and colorectal cancer].

Objective: To investigate the etiological role of hMLH1 gene A655 polymorphism in colorectal cancer.

Methods: A case-control study was carried out, including 115 colorectal cancer patients and 135 healthy people as control. Genomic DNA was extracted from peripheral white blood cell from all the subjects. Polymorphism was detected by PCR-based DHPLC analysis and verified by DNA sequencing.

Results: The hMLH1 gene A655G polymorphism was detected in 3.0% of healthy people and 11.3% of colorectal cancer patients (P<0.01), and the difference was significant (P<0.01). The hMLH1 gene A655G polymorphism was detected in 8.2% of tubular adenocarcinoma or tubular-papillary adenocarcinoma and 27.8% of mucinous adenocarcinoma, which was also significant (P<0.05).Meanwhile, hMLH1 gene A655G polymorphism was not associated with age, gender and lymphatic metastasis (all P>0.05).

Conclusions: The hMLH1 gene A655G polymorphism may play a role in the pathogenesis of colorectal cancer. Determination of the polymorphism may be a potential marker to predict the prognosis of colorectal cancer patients.