Cost 
$1,980.00
TAT 
4 weeks
CPT Code 
81407
Test Code 
1131
Test Methods 
Sequencing
Specimen Types Accepted 
Blood
Saliva
Buccal
Cultured Cells
Extracted DNA
Genes 

L1 syndrome is the most common cause of congenital hydrocephalus and accounts for about 5-10% of males with congenital hydrocephalus. The phenotypic spectrum of L1 syndrome, which can range from severe to mild, includes X-linked hydrocephalus [OMIM#307000], MASA syndrome [mental retardation, aphasia, shuffling gait and adducted thumbs, OMIM#303350] and X-linked corpus callosum agenesis [OMIM#304100]. In less severely affected males, hydrocephalus may be subclinically present and only documented because of developmental delay. Intellectual disability ranges from mild to moderate. Intra- and interfamily phenotypic variations have been reported.

Mutations in the L1CAM [OMIM#308840] gene are a cause L1 syndrome. The majority of mutations in L1CAM are private (unique to each family) and all types of disease-causing mutations have been identified: nonsense, frameshift, splice-site and missense mutations. L1CAM codes for the neural L1 cell adhesion molecule and is involved in cell-to-cell adhesion at the cell surface.