L1 family

The members of the L1-family in humans are called L1 or L1cam, CHL1 (close homologue of L1), Neurofascin and NRCAM (NgCAM related cell adhesion molecule).

NrCAM and neurofascin both have class 1 PDZ domain binding motifs at their COOH termini.

In extreme cases, babies are born with a fatal condition of hydrocephalus ("water on the brain").

Children with less severe mutations typically exhibit mental retardation and difficulty in controlling limb movements (spasticity).

The absence of such nerve tracts suggests that L1 is involved in the growth of axons within the embryonic nervous system.