neurodevelopmental disorder with central hypotonia and dysmorphic facies HDAC4-related haploinsufficiency syndrome https://github.com/monarch-initiative/mondo/issues/8897 brachydactyly mental retardation syndrome MONDO:1060110 HDAC4-related haploinsufficiency syndrome This term is more specific because it includes brachydactyly that is not characterized in the parent term. https://www.clinicalgenome.org/affiliation/40006/ A disorder caused by haploinsufficiency of HDAC4 and is characterized by brachydactyly type E, variable mild to moderate intellectual disability, seizures, autism spectrum disorder, short stature, obesity, and facial dysmorphism. Individuals with the gain of functions variants typically do not have brachydactyly and do have more consistent intellectual disability. brachydactyly intellectual disability syndrome