 lafora disease is a form of progressive myoclonic epilepsy with autosomal recessive transmission . 
 two genes have been identified so far : epm2a and nhlrc1 , and a third gene , concerning a pediatric onset subform , has been recently proposed . 
 we report the case of a 23-year - old woman of turkish origin with an unusual disease course . 
 clinical onset was at the age of 19  years with tonic  
 clonic seizures , followed by cognitive impairment ; eeg was in favor of lafora disease , and the mutation c.436g > a ( a missense mutation substituting aspartic acid in asparagine ) in the nhlrc1 gene confirmed this diagnosis . 
 after 5  years of evolution , the patient only has moderate cognitive impairment . 
 some nhlrc1 mutations , particularly c.436g > a , are associated with a slower clinical course , but there are conflicting data in the literature . 
 this case strengthens the hypothesis that the c.436g > a mutation in the nhlrc1 gene leads to less severe phenotypes and late - onset disease . 
Conflict of interest