MASA SYNDROME IS DUE TO MUTATIONS IN THE NEURAL CELL-ADHESION GENE L1CAM

MASA syndrome is a recessive X-linked disorder characterized by mental retardation, adducted thumbs, shuffling gait, aphasia and, in some ca ses, hydrocephalus. Since it has been shown that X-linked hydrocephalu s can be caused by mutations in L1CAM, a neuronal cell adhesion molecu le, we performed an L1CAM mutation analysis in eight unrelated patient s with MASA syndrome. Three different L1CAM mutations were identified: a deletion removing part of the open reading frame and two point muta tions resulting in amino acid substitutions. L1CAM, therefore, harbour s mutations leading to either MASA syndrome or HSAS, and might be freq uently implicated in X-linked mental retardation with or without hydro cephalus.