aphonia-deafness-retinal dystrophy-bifid halluces-intellectual disability syndrome (Monarch Disease Ontology entry MONDO_0017934) is a rare, genetic, multiple congenital anomalies/dysmorphic syndrome characterized by moderate to severe intellectual disability, congenital aphonia, hearing loss, optic atrophy, retinal dystrophy, broad thumbs and duplicated halluces. Facial dysmorphism (incl. thick eyebrows, ptosis, long, downslanting palpebral fissures, microstomia, low-set, posteriorly rotated ears) and genital abnormalities are also associated. Also known as: aphonia-deafness-retinal dystrophy-duplicated halluces-intellectual disability syndrome, aphonia-hearing loss-retinal dystrophy-duplicated halluces-intellectual disability syndrome.