| An extremely rare inherited form of progressive myoclonic epilepsy with characteristics of progressive myoclonus epilepsy and Lafora bodies, with an early onset (at around 5 years) and a prolonged disease course. Other manifestations include progressive dysarthria, ataxia, cognitive decline, psychosis, dementia, spasticity, dysarthria, myoclonus, and ataxia. The disease course typically extends for several decades. There is evidence the disease is caused by homozygous mutation in the PRDM8 gene on chromosome 4q21. |
