Are c.436G>A mutations less severe forms of Lafora disease? A case report

• Main Authors: Hélène-Marie Lanoiselée, Pierre Genton, Gaetan Lesca, Florence Brault, Bertrand De Toffol
• Format: Article
• Language: English
• Published: Elsevier 2014-01-01
• Series: Epilepsy and Behavior Case Reports
• Subjects: Lafora disease; Progressive myoclonic epilepsy; EPM2A; EPM2B; NHLRC1
• Online Access: http://www.sciencedirect.com/science/article/pii/S2213323213000467

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.