Association between papillary thyroid cancer and XRCC6 gene polymorphisms in the Turkish population.

Abstract

Background/aim: To investigate the association between the rs2267437, rs5751129 and rs132770 polymorphisms of the XRCC6 gene, which plays a role in repairing DNA double-strand breaks, and the risk of papillary thyroid carcinoma (PTC).

Materials and methods: The study included 150 patients who had been diagnosed with PTC and 204 healthy controls. Genotyping of the SNPs was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results: In the rs2267437 polymorphism, individuals with the GG genotype had lower risk of PTC than those with the wild-type CC genotype (p = 0.037, 95% CI: 0.19-0.96, OR: 0.67). The combined genotypes CG+GG were related to a reduced risk of PTC compared to the wild-type CC genotype (p = 0.023, 95% CI: 0.40-0.94, OR: 0.61) in the recessive model (GC+GG vs. CC). In addition, a query of the genotype-tissue expression (GTEx) database showed that the rs2267437 polymorphism may alter the expression level of XRCC6 in whole blood (p = 0.0009) but not in thyroid tissue. There were no significant associations between the rs5751129 and rs132770 polymorphisms and PTC.

Conclusion: This study demonstrated that rs2267437 polymorphism may have a protective effect against PTC in the Turkish population. However, the rs5751129 and rs132770 polymorphisms were not associated with the disease.