CNTN3 encodes Contactin 3, a member of the immunoglobulin/fibronectin superfamily of adhesion molecules. This protein mediates cell surface interactions and is believed to play a role in nervous system development. The exact function of CNTN3 is yet to be fully characterized. However, its paralogs contactin 1 and contactin 2 are known to be involved in neural cell migration, axon guidance and myelin subdomain organization.