Document Type: Research Articles
Department of Biochemistry, Neyshabur Medical Sciences Branch, Islamic Azad University, Neyshabur, Iran.
Department of Radiation Oncology, Reza Radiotherapy Oncology Center, Mashhad, Iran.
Department of Biotechnology, Neyshabur Branch, Islamic Azad University, Neyshabur, Iran.
Background: Colorectal cancer (CRC) is highly prevalent cancer, which should be genetically studied among
different peoples of the world. Objective: The aim of this study was to evaluate the effect of XRCC3T241M, XRCC3
A17893G and, for the first time, XRCC7 I3434T polymorphisms on CRC risk in Khorasan Razavi Province, Iran.
Materials and Methods: In this case-control study, 180 patients with CRC and 160 sex- and age-matched healthy
controls were studied. Genotypes were determined by RFLP-PCR and ARMS-PCR. Results: The incidence of CRC was
observed to be significantly more in a heterozygous XRCC3 C/T genotype than in the CC genotype (OR 2.210, 95% CI
1.073-4.548, p=0.030). In the case of the XRCC7 I3434T polymorphism, CRC risk was significantly (4.3 fold) higher
in I/T+T/T variant subjects compared to the I/I genotype (OR 4.394, 95% CI 2.721-7.096, p=0.000). Moreover, the
XRCC3 A17893G polymorphism did not correlate with CRC. In addition, there was no significant difference between
the distribution of genotypes of the three studied polymorphisms with demographic and clinicopathological features
in the CRC patients. Conclu