Neural cell adhesion molecules play an important role in neural cell interactions and neuronal development and growth. Close Homolog of L1 (CHL1), also designated cell adhesion molecule with homology to L1CAM or L1 cell adhesion molecule 2, belongs to the L1 gene family of neural cell adhesion molecules. CHL1 plays a role in signal transduction pathways and is involved in cell migration, axon growth and guidance. It is required for neuronal positioning and dendritic growth of pyramidal neurons in the posterior region of the developing mouse neocortex. CHL1 is expressed in pyramidal neurons in a high-caudal to low-rostral gradient within the developing cortex.