15q13.3 microdeletion (microdel15q13.3) syndrome is characterized by a wide spectrum of neurodevelopmental disorders with no or subtle dysmorphic features. The disease is MONDO_0012774 (chromosome 15q13.3 microdeletion syndrome). Also known as: 15q13.3 microdeletion syndrome, Del(15)(q13.3), monosomy 15q13.3.