The CNTN5 gene encodes contactin 5, a member of the immunoglobulin/fibronectin superfamily of adhesion molecules. CNTN5 is a glycosylphosphatidylinositol (GPI)-anchored neuronal membrane protein and like other contactins, it mediates cell surface interactions during nervous system development. While the exact function of CNTN5 is yet to be fully characterized, its paralogs contactin 1 and contactin 2 are known to be involved in neural cell migration, axon guidance and myelin subdomain organization.