Abstract
Background: The xeroderma pigmentosum group D (XPD) gene plays a key role in nucleotide excision repair pathway of the damaged DNA. Genetic polymorphisms in coding region of XPD gene may alter DNA repair capacity of the protein and hence can modulate the risk of colorectal cancer (CRC) risk. The aim of the study was to determine the genetic association of XPD Lys751Gln polymorphism with the risk of CRC development. Materials and Methods: One hundred and twenty CRC patients and 160 normal controls were assessed for genotype frequencies of XPD Lys751Gln polymorphism. We used polymerase chain reaction-restriction fragment length polymorphism technique to assess the XPD Lys751Gln polymorphism. Results: We observed a significant association (P < 0.05) between the XPD Lys751Gln polymorphism and the risk of developing CRC (P < 0.05). In addition, Gln/Gln genotype of XPD gene doubled the risk for the development of CRC (P < 0.05; odds ratio = 2.25, 95% confidence interval [1.07-4.7]). Conclusions: Our results suggest that there is a significant association between the XPD Lys751Gln polymorphism and the risk of CRC.