Megalencephaly-Polymicrogyria-Polydactyly-Hydrocephalus Syndrome 1, also known as megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome, is related to megalencephaly-polymicrogyria-postaxial polydactyly-hydrocephalus syndrome and megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome 2, and has symptoms including seizures An important gene associated with Megalencephaly-Polymicrogyria-Polydactyly-Hydrocephalus Syndrome 1 is PIK3R2 (Phosphoinositide-3-Kinase Regulatory Subunit 2). Affiliated tissues include brain and tongue, and related phenotypes are hydrocephalus and ventriculomegaly