Abstract
Background: Breast cancer is a major public health problem around the world, including Thailand and it has the highest ranking among female cancer. Currently, the diversity or polymorphism of ERCC1 gene (excision repair cross-complementary group 1 gene or ERCC1) was reported to associate with an increased risk of breast cancer. This study aims to investigate the relationship between ERCC1 polymorphism and the breast cancer risk in the lower northeastern region women of Thailand. Materials and Methods: One hundred fifty one samples from breast cancer patients and 120 samples from healthy control group were analysed. Genomic DNA was extracted from white blood cell of all samples. The real-time polymerase chain reaction (qPCR) was used to demonstrate genetic polymorphism of ERCC1. Results: The results showed that the ERCC1 rs11615 polymorphism variant AG was associated with an increased risk of breast cancer. This study demonstrated that the frequency of ERCC1 rs11615 in patients with breast cancer was higher than healthy control group. The ERCC1 polymorphism variant AG carrier presented 3.53-folds high risk of breast cancer [odds ratio (OR) = 3.53, 95% CI = 1.61-7.74, P = 0.001]. In addition, when age, menopause period, number of child, smoking and alcohol drinking were adjusted, the ERCC1 rs11615 variant AG carrier was associated with increased breast cancer risk to 3.97 folds, with OR = 3.79, 95% CI = 1.62-8.84, P = 0.002. Conclusions: This study showed that ERCC1 rs11615 genotype AG was associated with breast cancer risk in the lower northeastern region women of Thailand.