IL4R (INTERLEUKIN 4 RECEPTOR) is a human gene that encodes the alpha chain of the interleukin-4 receptor, a type I transmembrane protein that can bind interleukin 4 and interleukin 13 to regulate IgE antibody production in B cells. The IL4R gene is localized to 16p12.1-p11.2 by in situ hybridization and Southern blot analysis of DNA from a panel of mouse-human somatic cell lines. IL4 plays a major role in immunoglobulin E (IgE) production. Its signal is conferred to effector cells through binding to the alpha chain of the IL4 receptor. IL4 interacts with IL4R with high affinity, leading to dimerization with either the common gamma chain,a component of receptors for a number of cytokines, to create a type I receptor, or with IL13RA1 to form a type II receptor.The IL4R gene contains 12 exons and IL4R is a complex of at least 2 components, one of which is a novel affinity converting subunit that is critical for cellular signal transduction. See also IL13RA1 and IL13RA2.