Association of IL17A rs4711998 and IL1B rs16944 Polymorphism with Anti-Thyroid Peroxidase Serum Level in Autoimmune Thyroid Diseases: A Case–Control Study in Iranian Population

<b><i>Background:</i></b> Autoimmune thyroid diseases (AITDs), including Hashimoto's thyroiditis and Graves' disease, are characterized by aberrant immune responses influenced by both genetic predisposition and environmental triggers. Genetic association studies have identified several candidate loci that may contribute to the onset and progression of these conditions. The present study investigates the potential impact of specific genetic polymorphisms in interleukin genes (IL17A, IL1B, IL18) and CTLA-4 on thyroid peroxidase antibody (TPOAb) levels in individuals from northwest Iran. <b><i>Results:</i></b> A total of 82 individuals with elevated TPOAb levels and 82 antibody-negative controls were genotyped for single nucleotide polymorphisms using the tetra-primer amplification refractory mutation system polymerase chain reaction. The analysis revealed significant associations between specific genetic variants and TPOAb levels. Notably, the AG genotype of IL17A rs4711998 was associated with a protective effect, whereas the AA genotype of IL1B rs16944 was correlated with elevated antibody levels, suggesting a potential role in enhancing autoimmune responses. <b><i>Conclusions:</i></b> These findings underscore the contribution of genetic variations in interleukin genes to the pathogenesis of AITDs in the northwest Iranian population. Elucidating these associations may enhance our understanding of disease mechanisms and contribute to the development of targeted therapeutic strategies.