Detected in the cytoplasm of chronic lymphocytic leukemia (CLL) cells. Specifically expressed in chronic lymphocytic leukemia (CLL) cells from patients without immunoglobulin heavy-chain hypermutations. Expression is detected in all CLL cells and levels are similar in patients before and after treatment. Tridimensional modeling predicts that it may interact with the IL-4 receptor. This protein has no orthologs in other species and appears to be the product of a protein-coding gene which has arisen since divergence from chimp.