label: Megalencephaly-Polymicrogyria-Polydactyly-Hydrocephalus Syndrome-1
label_lc: megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome-1
description: An autosomal dominant condition caused by mutation(s) in the PIK3R2 gene, encoding phosphatidylinositol 3-kinase regulatory subunit beta. It is characterized by mild to severe intellectual disability, megencephaly, polymicrogyria, and postaxial polydactyly.