Özet:

Objective: Colorectal carcinoma (CRC) is the third most frequent cancer in the world and a heterogenious disease which aroze from one or a combination of different genetic mechanisms. The multiple drug resistance-1 (MDR1) gene which encodes P-glycoprotein (P-gp) plays a part in the bioavailability of drugs and cell toxicity. In the current study, we aimed to investigate the possible relation between the MDR1 gene C3435T polymorphism and CRC risk in the Turkish population. Material and Methods: Forty three patients (26 men, 17 women) with CRC and 48 healthy controls (34 men, 14 women) were included in the study. The MDR1 C3435T genotypes were determined by the Restriction Fragment Length Polymorphism (RFLP) method. Results: Statistical significance was obtained in terms of genotype distributions of MDR1 C3435T genotypes between study groups. The frequencies of MDR1 C3435T CC, TT and CT genotypes in the CRC patient group were found as 16.3%, 32.6% and 51.2%, respectively. The frequency of the homozygous TT genotype was found as 32.6% in CRC patients while it was identified as 14.6% in controls (p=0.04; OR=2.82, 95% CI: 1.01-7.87). When the patients were compared with the healthy population, TT genotype carriers of MDR1 C3435T polymorphism were found at 2.8-fold (p<0.05 ) increased risk for the development of CRC. Conclusion: Our results show that the MDR1 C3435T polymorphism might be one of the genetic risk factors for CRC development in the Turkish population.