Abstract
The aim of this study was to investigate the association between signal transducer and activator of transcription 3 (STAT3) polymorphisms and autoimmune thyroid diseases and clinical features. We genotyped six single-nucleotide polymorphisms (SNPs) rs1053005, rs2293152, rs744166, rs17593222, rs2291281, and rs2291282 of STAT3 gene in 667 patients with autoimmune thyroid disease (417 Graves' disease (GD) and 250 Hashimoto's thyroiditis (HT)) and 301 healthy controls. The allele A from rs1053005 was significantly less frequent in both GD and HT patients (P = 0.0024, OR = 0.6958, 95%CI = 0.5508-0.8788; P = 0.0091, OR = 0.7013, 95%CI = 0.5397-0.9112, respectively). The AA genotype of rs1053005 was less in GD and HT patients too (P = 0.0025,OR = 0.6278, 95%CI = 0.466-0.847) and (P = 0.0036,OR = 0.601, 95%CI = 0.428-0.843). The allele G from rs17593222 increased the susceptibility to the ophthalmopathy development both in autoimmune thyroid disease (AITD) and GD patients (P = 0.0007, OR = 3.980, 95%CI = 1.871-8.464; P = 0.0081, OR = 3.378, 95%CI = 1.441-7.919, respectively). The allele A and AA genotype of SNP rs1053005 may protect individuals from the susceptibility to AITD and their frequency decreased in AITD patients. In addition, the allele G of rs17593222 may increase the ophthalmopathy risk in AITD patients. Our findings suggest the existence of association between STAT3 gene and AITD, thus adding STAT3 gene to the list of the predisposing genes to AITD.