CTLA4 and autoimmune thyroid disease: A solid correlation between autoimmune thyroid diseases and CTLA-4 polymorphism on chromosome 2q33 was proved by Bicek et al. in 2009, namely two A>G polymorphisms of a single nucleotide of CTLA-4 gene at position +49 of exon 1 (49A/G) and +6230 (CT60) in 3’UTR [26].