Association Study of rs2987983 Polymorphism in the Promoter Region of ESR2 Gene and Susceptibility to Nodular Thyroid inWomen of Markazi Province, Iran

Background: The risk of thyroid disease has been increased during recent years; more than 200 million people are suffering from various types of thyroid diseases. The rate of thyroid nodules in women is 4 times more than that of men. Epidemiological findings and experimental evidence of thyroid lesions suggest that sex hormones, especially estrogen, may affect this gland and its neoplasms. Objectives: Considering the prevalence of benign and malignant thyroid disease in women, we investigated the association between rs2987983 polymorphism in the estrogen receptor beta gene and nodular thyroid disease. Methods: In this case-control study, 146 patients with thyroid nodules from Amir- Almomenin Hospital in Arak were compared with 151 healthy individuals. The diagnosis was performed by ultrasonography and confirmed by an endocrinologist. After DNA extraction, genotyping was performed with T-ARMS PCR. Finally, statistical analysis was carried out. Results: The frequencies of AA, AG, and GG genotypes in the case group were 48 (32.9%), 83 (56.8%), and 15 (10.3%), respectively. These values in the control group were 64 (42.4%), 64 (42.4%), and 23 (15.2%), respectively. Overall, a statistically significant association (P =0.042, χ² = 6.3, df = 2) was observed between rs2987983 polymorphism and thyroid nodules. Conclusions: Considering the significant association between rs2987983 polymorphism and thyroid nodules, it can be suggested that the mentioned polymorphism may be used as a diagnostic biomarker. Because this polymorphism is in the promoter region of the gene, it probably alters gene expression levels.