Abstract: Background:Single nucleotide polymorphisms in mismatch repair genes may be associated with different protein expression, production, and efficiency according to allele status and influence the risk of developing colorectal cancer. Objective:This research aimed at analyzing two important polymorphisms in MLH1 gene and their association in colorectal cancer susceptibility. Methods:In total, 219 CRC patients and 248 healthy controls were genotyped with PCR/RFLP for I219V and IVS12-169 C>T polymorphisms in MLH1 gene. Sequencing performed to ensure work flow and results. We used unconditional logistic regression after adjusting for age and sex to evaluate the association between each polymorphism and colorectal cancer. Results:The MLH1 I219V polymorphism was associated with colorectal cancer susceptibility (P=0.01). Stratified data analysis for gender demonstrated association of AG (P=0.009) and GG (P=0.021) genotypes with risk of colorectal cancer in women. In contrast there is no association with IVS 12-169 C>T polymorphism and colorectal cancer risk. Conclusions:I219V SNP might be a susceptibility factor for CRC and gender is a factor that must be considered when it is analyzing. Further tests need to be done to define it as a dependable prognosis factor.
