Gene associated with seizures, autism, and hepatomegaly in an Amish girl.

A genetic defect causing autism and epilepsy involving the contactin associated protein-like 2 gene (CNTNAP2) has been discovered in a selected cohort of Amish children. These children were found to have focal seizures and autistic regression. Surgical biopsy of the anterior temporal lobe of two such children revealed cortical dysplasia and a single nucleotide polymorphism mutation of this gene. The present case is that of a related but geographically distant proband with a similar phenotype but a single-base-pair deletion in the CNTNAP2 gene. This patient exhibited the additional features of periventricular leukomalacia and hepatomegaly.