Intellectual Developmental Disorder, Autosomal Recessive 24, is also known as mental retardation, autosomal recessive 24. An important gene associated with Intellectual Developmental Disorder, Autosomal Recessive 24 is MRT24 (Mental Retardation, Non-Syndromic, Autosomal Recessive, 24). Related phenotypes are delayed speech and language development and microcephaly