This gene encodes a G-protein-coupled receptor that is preferentially expressed in CD4+ effector T helper 2 (Th2) cells. This protein is a prostaglandin D2 receptor that mediates the pro-inflammatory chemotaxis of eosinophils, basophils, and Th2 lymphocytes generated during allergic inflammation. Single nucleotide polymorphisms in the 3' UTR of this gene have been associated with asthma susceptibility.[provided by RefSeq, Mar 2011].