The interleukin 2 (IL2) receptor alpha (IL2RA) and beta (IL2RB) chains，together with the common gamma chain (IL2RG)，constitute the high-affinity IL2 receptor. Homodimeric alpha chains (IL2RA) result in low-affinity receptor，while homodimeric beta (IL2RB) chains produce a medium-affinity receptor. Normally an integral-membrane protein，soluble IL2RA has been isolated and determined to result from extracellular proteolyisis. Alternately-spliced IL2RA mRNAs have been isolated，but the significance of each is presently unknown. Mutations in this gene are associated with interleukin 2 receptor alpha deficiency.[provided by RefSeq，Nov 2009].