The DSCAM gene encodes a member of the immunoglobulin superfamily of cell adhesion molecules. Members of this family localize on the surface of cells and help in binding cells to each other or with the extracellular matrix. The DSCAM protein is specifically involved in neuronal self-avoidance, an essential mechanism during arborisation and axon branching, wherein it promotes repulsion between neuronal projections from the same type of cells in order to avoid clumping or fasciculation. By carrying out its function, DSCAM is believed to play a role in several developmental processes of the nervous system such as synapse assembly, dendrite morphogenesis, axon guidance and retina layer formation.
Overexpression or duplication of the DSCAM gene region has been linked to cases of Down Syndrome and Congenital Heart Disease (DSCHD), a condition characterized by mental retardation, characteristic facies and major congenital malformations such as atrioventricular septal defects.