Exploring The Link Between TSHR Gene Polymorphism and Thyroid Function Parameters in Thyroid Disorder Patients

Background and Objectives: Most common autoimmune thyroid diseases are Hashimoto's thyroiditis and Graves' disease which are caused by immune system and genetic factors. In this study the association between the thyroid function test (TFT) values and the TSHR gene polymorphism c.1349G>T will be investigated, which leads to a p.Arg450Leu amino acid change, in patients with thyroid disorders. Methods: A cross-sectional study investigating, 50 thyroid dysfunction patients and 50 samples of healthy controls participated. The immunoassay was used to measure the serum levels of TSH, FT3, and FT4. Allele-specific ARMS-PCR was used to genotype the TSHR c.1349G>T (p.Arg450Leu) polymorphism. Results: Hyperthyroid patients displayed suppressed TSH and raised FT3/FT4 levels, and hypothyroid patients displayed considerably elevated TSH and decreased FT3/FT4 levels. The hyperthyroid group had a higher frequency of the c.1349G>T variation of the TSHR gene (p.Arg450Leu) than the hypothyroid and control groups. The T allele was found to be statistically significantly associated with a higher incidence of hyperthyroidism (P<0.01). Serum TSH levels did not significantly differ between homozygous and heterozygous carriers of the mutation. Conclusion: The research suggests a possible relationship between thyroid dysfunction, specifically hyperthyroidism, and the TSHR c.1349G>T (p.Arg450Leu) polymorphism. Thyroid disease risk prediction and diagnosis accuracy may be improved by performing genetic screening. Keywords: ARMS-PCR with TFTs, Hormone levels, hyperthyroidism, polymorphism, TSHR gene