METAP1 Mutation Is a Novel Candidate for Autosomal Recessive Intellectual Disability

Intellectual disability (ID) is a genetic and clinically heterogenous common disease and underlying molecular pathogenesis can frequently not be identified by whole- exome/genome testing. Here, we report 4 siblings born to a consanguineous union who presented with intellectual disability and discuss the METAP1 pathway as a novel etiology of ID. Genomic analyses demonstrated that patients harbor a novel homozygous nonsense mutation in the gene METAP1. METAP1 codes for methionine aminopeptidase 1 (MetAP1) which oversees the co-translational excision of the first methionine remnants in eukaryotes. Loss of function mutations to this gene may result in a defect in the translation of many essential proteins within a cell. Improper neuronal function resulting from this loss of essential proteins could lead to neurologic impairment and ID.