Objective: Polymorphisms in methylenetetrahydrofolate reductase (MTHFR), such as MTHFR C677T and A1298C, are associated with several cancers. This study aimed to evaluate the effects of MTHFR polymorphisms on colorectal cancer risk in a population from damitta Egypt. Methods. This hospital-based case-control study was conducted during 2008-2010; 64 colon cancer cases and 90 controls were enrolled. Information was collected and blood samples were obtained for assay of MTHFR C677T and A1298C polymorphisms by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and PCR-restriction fragment length polymorphism (PCR-RFLP) techniques. Associations between variables of interest and colorectal cancer were assessed using conditional logistic regression. Results: Increased risk of colorectal cancer was associated with the MTHFR C677 TT genotype of C677T polymorphism (OR(adj) = 24.0; 95% CI: 1.34-429.1; P value for interaction = 0.001) . The 1298AC genotype and C allele was associated with a statistically significant lower risk among subjects (OR, 3.85; 95% CI, 1.78-8.33; P value for interaction=.0005 and OR,1.88 ;95% CI, 1.16-3.059 P value for interaction=0.01), respectively. MTHFR 1298 AA genotype and A allele was found to be associated with a significantly decreased risk for colorectal cancer (OR = 0.25, 95% CI 0.11- 0.52; P value for interaction= 0.0005 and OR = 0.52, 95% CI 0.32-0.85 P value for interaction= 0.01and ), respectively . There was no clear relation between colorectal adenomas and those with the 1298 CC genotype. The combined CC , AA [corrected] genotypes and the CT+AA [corrected] genotypes and the TT+ AC were associated with a statistically significant lower risk for developing colorectal cancer (P value for interaction= 0.03 , 0.02 , 0.001), respectively .
CONCLUSIONS: The findings suggest an interaction between the MTHFR genotype and colorectal adenomas among Egyptian patients.
Abbreviations: T2DM: Colorectal cancer– MTHFR: methylenetetrahydrofolate reductase – SNP: single nucleotide polymorphism- SSP-PCR: sequence specific primer- polymerase chain reaction.
Key words: MTHFR gene - Colorectal cancer.