Severe, de novo phenotype in females: X-linked mental retardation and microcephaly with pontine and cerebellar hypoplasia [OMIM #300749] is characterized by severe or profound mental retardation (MR), microcephaly, and disproportionate pontine and cerebellar hypoplasia in females. These mutations are typically de novo and thought to be lethal in males. Mild, familial phenotype in males: Affected males have mild to moderate MR, and carrier females seem to be unaffected. In 2 families, MR was accompanied by nystagmus in multiple affected individuals. CASK mutations were detected in 4/46 individuals with MIC-PCH including 3/13 females and 1/33 males. A resequencing screen of X-chromosome coding exons in individuals from approximately 350 families with X-linked MR revealed CASK mutations in 4 families. Sequencing of CASK can be ordered as a single test, or as part of our Cerebellar Hypoplasia Panel, or our X-Linked and Comprehensive Intellectual Disability Panels. Please see our information sheets for more details.
Specimen Types Accepted