The CT60 polymorphism of CTLA-4 maps an important genetic determinant for the risk of both GD and HT across diverse populations.

Alpha‐subunit of the IL‐2 receptor (IL‐2Rα) encoded by the IL2RA/CD25 gene binds IL‐2 that plays a pivotal role in the regulation of T cell function. Levels of a soluble form of IL‐2Rα (sIL‐2Rα) lacking the transmembrane and cytoplasmic domains were shown to be increased in several autoimmune diseases including Graves’ disease (GD). Recent studies showed association between the IL2RA/CD25 gene variants and several autoimmune diseases including GD. In this study, we analyzed whether polymorphic markers rs2104286, rs41295061, and rs11594656 located at the IL2RA/CD25 locus confer susceptibility to GD and are related to increased concentrations of sIL‐2Rα. A total of 1474 Russian GD patients and 1609 control subjects were genotyped for rs2104286, rs41295061, and rs11594656 using a Taqman assay. Concentrations of sIL‐2Rα in sera of affected and non‐affected individuals were measured using an ELISA test. A minor allele A of rs41295061 showed significant association with increased risk of GD [odds ratio (OR) = 1.43, Pc = 0.00102]. The allele A of rs41295061 and allele A of rs11594656 constitute a higher risk haplotype AA (OR = 1.47, Pc = 0.0477). Compared to carriers of the protective haplogenotype GT/GT, the carriage of two copies of the haplogenotype AA/AA was associated with elevated levels of sIL‐2Rα in both GD patients (AA/AA versus GT/GT: 1.35 ± 0.47 ng/ml versus 1.12 ± 0.45 ng/ml, P = 0.0065) and healthy controls (AA/AA versus GT/GT: 0.67 ± 0.28 ng/ml versus 0.51 ± 0.33 ng/ml, P = 0.0098). This is the first report presenting correlation between the carriage of disease‐associated variants of IL2RA/CD25 with increased levels of sIL‐2Rα in GD.

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With a relative failing of linkage and candidate gene association studies, there has been much sceptism about the ability of geneticists to identify genes for common, complex disorders. In the field of the genetics of type 1 diabetes (T1D), more than twenty years of labor-intensive and cost-expensive effort has resulted in the identification of only four T1D