15q13.3 microdeletion (microdel15q13.3) syndrome is characterized by a wide spectrum of neurodevelopmental disorders with no or subtle dysmorphic features. The disease is 15q13.3 microdeletion syndrome (Orphanet rare-disease nomenclature identifier Orphanet_199318). Also known as: Del(15)(q13.3), Monosomy 15q13.3.