Association of XRCC1 and OGG1 DNA repair gene polymorphisms with rheumatoid arthritis in Egyptian patients

• XRCC1 polymorphisms may increase the susceptibility of an individual to have RA.
• OGG1 polymorphism may increase the susceptibility of an individual to have RA.
• XRCC1 polymorphisms more likely to cause bone erosion in RA patients.

Rheumatoid arthritis (RA) is a chronic autoimmune disease and can lead to deformities and severe disabilities, due to irreversible damage of tendons, joints, and bones. Previous studies indicated that the DNA repair system was involved in the pathology of RA. In this study, we investigated the association of two XRCC1 (X-ray repair cross-complementing group 1) (rs25487 and rs25489) gene polymorphisms and two OGG1 (8-oxoguanine glycosylase 1) gene polymorphisms (rs159153 and rs3219008) with the susceptibility to RA in 320 Egyptians individuals (160 RA patients and 160 controls). Genotyping was performed using restriction fragment length polymorphism polymerase chain reaction. We found an association between variant XRCC1 (rs25487 and rs25489) genotype polymorphisms, OGG1 (rs3219008) genotype polymorphism, and RA disease susceptibility. Moreover, the presence of the Gln/Gln, Arg/His, and His/His genotypes of XRCC1 was significantly more likely to have bone erosion and extra-articular features in RA patients. Further, patient's carrying the OGG1 A/G and G/G genotypes more likely to have bone erosion. However, the AA genotype and A allele were significantly more likely to have extra-articular features. Also, there were no significant associations between C/T OGG1 gene polymorphism and RA susceptibility, bone erosion, and extra-articular features occurrence in RA patients. We concluded that the XRCC1-Arg/Gln, XRCC1-Arg/His, and OGG1 A/G polymorphism have a role in the development of rheumatoid arthritis disease. Also, these variant are associated with the severity of RA.