Protocadherins are a large family of cadherin-like cell adhesion proteins that are involved in the establishment and maintenance of neuronal connections in the brain. There are three protocadherin gene clusters designated alpha, beta and gamma, all of which contain multiple tandemly arranged genes. PCDHGA2 (Protocadherin gamma A2) is a 932 amino acid protein that is one of 22 proteins encoded by the protocadherin gamma cluster. The protocadherein gamma cluster consists of three subfamilies (A, B and C) and PCDHGA2 is a member of the gamma subfamily A. PCDHGA2 contains six cadherin motifs, and characteristic of gamma protocadherins, PCDHGA2 is a type I transmembrane receptor expressed in the central nervous system and localizes to synapses. Members of the gamma cluster of protocadherins are essential for neuronal survival.