Background: Coronary Artery Disease (CAD), which is a multifactorial genetic disease,
is known as one of the most common causes of death worldwide. In this regard, X-ray Repair
Cross-Complementing group 1 (XRCC1), a DNA repair protein involved in Single-Strand Breaks
(SSBs), and Base Excision Repair (BER) pathways have been reported to be responsible for the efficient
repair of single strand breaks and damaged bases in DNA.
Objectives: In the current study, we analyzed Arg399Gln (rs25487), which is one of the most common
polymorphisms of XRCC1 gene that might be associated with the increased risk for CAD.
Methods: This case-control study was performed to investigate the relationship between this polymorphism
and CAD development. In this study, 290 patients and 216 controls were diagnosed by
cardiac angiography and then screened for the above-mentioned polymorphism using Restriction
Fragment Length Polymorphisms (RFLP) method.
Results: The frequency of the GA genotype of XRCC1 Arg399Gln (rs25487) was significantly
higher in CAD patients compared to the controls (p=0.002, OR: 1.21, 95% CI: 1.06-1.37). Moreover,
its dominant mode (AA + GA) genotype had a 1.851-fold increase in the risk of CAD (p =
Conclusion: Our findings demonstrated that Arg399Gln polymorphism of XRCC1 (rs25487) has a
significant relationship with CAD and also plays a probable predisposing role in that. Our results
support the role of DNA damages and the malfunctions of DNA repair system in the patients with