MedGen

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]

Ring chromosome 17 syndrome is a rare chromosomal anomaly syndrome, resulting from partial deletion of chromosome 17, characterized by highly variable manifestations, ranging from a severe phenotype which presents with lissencephaly and severe intellectual disability to a milder phenotype that includes short stature, microcephaly, intellectual disability, seizures (that may be pharmacoresistant), café-au-lait spots, retinal flecks and minor facial dysmorphism, depending on the presence or absence of the Miller-Dieker critical region. [from ORDO]