301-519-2100 • FAX 301-519-2892 • 207 PERRY PARKWAY GAITHERSBURG, MD 20877  
 
  
SEARCH

X-linked Hydrocephalus / L1 Disease Spectrum

  • Congenital stenosis of the aqueduct of Sylvius
  • MASA Syndrome
  • CRASH Syndrome
These related neurological syndromes with X-linked inheritance are allelic and all due to mutation in the L1CAM gene. Congenital hydrocephalus and resultant macrocephaly associated with aqueductal stenosis may occur in isolation but is frequently associated with other features, including adducted thumbs, developmental delays including mental retardation, and spastic paraplegia. MASA syndrome includes Mental retardation, Aphasia, Shuffling gait, and Adducted thumbs. CRASH syndrome includes Corpus callosum agenesis/hypoplasia, Retardation, Adducted thumbs, Spastic paraplegia, and Hydrocephalus. There can be significant phenotypic variability within families, with some males being severely affected and diagnosed already during pregnancy, while others may have no macrocephaly and long survival. Five percent of females with a L1CAM mutation present with variable clinical symptoms.

Analysis is performed by bi-directional sequence analysis of the entire coding region (exons 1-28) including splice site junctions of the L1CAM gene. L1CAM mutations are present in 15-25% of males who have sporadic, isolated hydrocephalus. 74-90% percent of males with hydrocephalus, a positive family history, and at least one other feature of L1CAM disease show mutations in this gene. In females, where sequencing fails to identify a pathogenic mutation, targeted array CGH analysis with exon-level resolution (ExonArrayDx) will be performed to evaluate for a deletion or duplication of one or more exons of the L1CAM gene. Note, this testing requires a BLOOD specimen. Carrier detection in at-risk female relatives and prenatal diagnosis is also available.

For more details please review the Information Sheet linked below:

Information Sheet, including prices and CPT codes Back to the List
X-linked hydrocephalus / MASA syndrome / CRASH syndrome. Prenatal Testing Services.  
Consent Document  
Genetic Test Sample Submission Form (Test Requisition Form) including Payment Options  
L1CAM, L1, MIC5, CAML1, agenesis corpus callosum, hydrocephalus, X-linked, adducted thumbs, spastic paraplegia, retardation, aqueductal stenosis, ventriculomegaly SPG1

© 2000 - 2012 GeneDx. All rights reserved.