Analysis of Chosen Polymorphisms Rs7138803 A/G- FAIM2, Rs7093069 C/T - IL-2RA, Rs5742909 C/T - CTLA-4 in Pathogenesis of Hashimoto’s Thyroiditis in Children

Introduction: Autoimmune thyroid diseases are multifactorial diseases with a genetic susceptibility and environmental factors. A potential role of the Fas apoptotic inhibitory molecule 2 (FAIM2) gene, the high‐affinity alpha subunit (CD25) of the interleukin‐2 receptor (IL-2RA) gene, the cytotoxic T cell antigen 4 (CTLA-4) gene polymorphisms on autoimmune thyroid diseases (AITDs) in children has not been established equivocally yet. Objective: To estimate the association of polymorphisms of FAIM2, IL-2RA and CTLA-4 genes with the predisposition to Graves’ disease (GD) and Hashimoto’s thyroiditis (HT) in children. Methods: The study was performed in 170 patients with GD, 81 with HT and 110 healthy volunteers from two endocrine centers (Białystok, Messina). The three single nucleotide polymorphisms (SNPs): Rs7138803-FAIM2, Rs7093069-IL-2RA and Rs5742909-CTLA-4 were genotyped by TaqMan SNP genotyping assay with platform QuanStudio 12K Flex - OpenArray plates using the realtime PCR. Results: Rs7138803 A/A genotypes were more frequent in HT and GD patients in comparison to healthy subjects (p=0.009 with OR=3.5; p<0.0075 with OR=2.9, respectively). Rs7138803 A alleles were more frequent in GD patients in comparison to healthy subjects (p=0.019 with OR=1.5). Rs7093069 C alleles were more frequent in HT patients in comparison to healthy subjects (p=0.032 with OR=1.61). That means that risk for development of HT is exactly 1.6 higher for C allele in comparison to T allele. Rs5742909 C alleles were more frequent in HT patients in comparison to healthy subjects (p=0.045 with OR=1.8). Conclusions: Rs7138803 A/G, Rs7093069 C/T and Rs5742909 C/T polymorphisms could contribute to development of HT in children. The main risk factor for rs7093069 and rs5742909 is allele C. In case of rs7138803 the main risk factor is allele A for development of both GD and HT.