Intellectual Developmental Disorder, Autosomal Recessive 9, also known as autosomal recessive intellectual developmental disorder 9/26, is related to autosomal recessive non-syndromic intellectual disability. An important gene associated with Intellectual Developmental Disorder, Autosomal Recessive 9 is MRT9 (Mental Retardation, Non-Syndromic, Autosomal Recessive, 9). Related phenotypes are intellectual disability and spasticity