Association Between IL-18 Gene Polymorphism and Hashimoto Thyroiditis

Background: Hashimoto’s thyroiditis (HT) is the most frequent organ-specific autoimmune disease (AIT), which is called lymphocytic thyroiditis in which T helper-1 lymphocytes mediate the disease. IL-18 is expressed in thyroid follicular cells (TFCs) during HT. The findings of studies aimed at investigating the relationship between IL-18 and HT are highly contradictory. In this study, we aimed to investigate the association between IL-18 gene polymorphism and HT.Methods and ResultsThe study was included 97 patients diagnosed with HT and 86 volunteers in the healthy control group. The IL18-607C/A (rs1946518) ve -137G/C (rs187238) genotypes were determined using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. No significant difference in the mean ages and gender was observed between the groups (p = 0.763 and p = 0.658, respectively). -137 IL18 CG genotype is higher in HT than controls. The risk of the IL-18 CG genotype for HT patients was more than 2.237 times higher (OR; 2.237 %95 Cl: 1.195–4.187, p = 0.039) compared to that of the G/G genotype. Also, -607 AC genotype is higher in the control group than in the HT group (in individuals with the IL18 CG genotype).ConclusionsAccording to our results, the CG genotype might be a risk factor for HT. Conversely, there is a possibility that the AC genotype also plays a protective role against the condition. However, further studies will contribute to the emergence of new solutions by revealing the molecular and cellular mechanisms of HT.