MedGen

ATN1-related neurodevelopmental disorder (ATN1-NDD) is characterized by developmental delay / intellectual disability. Other neurologic findings can include infantile hypotonia, brain malformations, epilepsy, cortical visual impairment, and hearing loss. Feeding difficulties, present in some individuals, may require gastrostomy support when severe; similarly, respiratory issues, present in some, may require respiratory support after the neonatal period. Distinctive facial features and hand and foot differences are common. Other variable findings can include cardiac malformations and congenital anomalies of the kidney and urinary tract (CAKUT). To date, 18 individuals with ATN1-NDD have been identified. [from GeneReviews]

Dentatorubral-pallidoluysian atrophy (DRPLA) is a progressive disorder of ataxia, myoclonus, epilepsy, and progressive intellectual deterioration in children and ataxia, choreoathetosis, and dementia or character changes in adults. Onset ranges from before age one year to age 72 years; mean age of onset is 31.5 years. The clinical presentation varies depending on the age of onset. The cardinal features in adults are ataxia, choreoathetosis, and dementia. Cardinal features in children are progressive intellectual deterioration, behavioral changes, myoclonus, and epilepsy. [from GeneReviews]