This gene encodes a member of the contactin family of immunoglobulins. Contactins are axon-associated cell adhesion molecules that function in neuronal network formation and plasticity. The encoded protein is a glycosylphosphatidylinositol-anchored neuronal membrane protein that may play a role in the formation of axon connections in the developing nervous system. Deletion or mutation of this gene may play a role in 3p deletion syndrome and autism spectrum disorders. Alternative splicing results in multiple transcript variants. [provided by RefSeq, May 2011]