The protein encoded by this gene is a cytokine that actsas a regulator of a variety of hematopoietic cells. This cytokinestimulates cell proliferation and prevents apoptosis. It functionsthrough the interleukin 9 receptor (IL9R), which activatesdifferent signal transducer and activator (STAT) proteins and thusconnects this cytokine to various biological processes. The geneencoding this cytokine has been identified as a candidate gene forasthma. Genetic studies on a mouse model of asthma demo