IL2RA and multiple sclerosis: IL-2 GWAS studies identified multiple polymorphisms affecting IL2 pathway genes encoding IL2Rα (CD25) and IL-2 as key genetic risk alleles in autoimmunity, corroborating IL2 as an essential cytokine for maintaining immune homeostasis (Vella et al, 2005;, International Multiple Sclerosis Genetics et al, 2007;,  Yamanouchi et al, 2007;, International Multiple Sclerosis Genetics, 2008;, Onengut-Gumuscu et al, 2015; , Wallace et al, 2015).