Department of Neurology with Institute of Translational Neurology, University Hospital Münster, Münster
Praxis für Humangenetik, Tübingen
Department of Neurology, Medical Park Bad Feilnbach, Bad Feilnbach, Germany
Correspondence: Lisa Langenbruch
Department of Neurology with Institute of Translational Neurology,
University Hospital Münster,
Gebäude A1, 48149 Münster,
Sleep-related hypermotor epilepsy, or nocturnal frontal lobe epilepsy, as it was formerly called, is a focal epilepsy with mostly sleep-related seizures of hypermotor, tonic or dystonic semiology. Sleep-related hypermotor epilepsy may be attributed to a monogenetic cause with autosomal dominant inheritance. Mutations are described in different genes, including the genes for three subunits of the nicotinic acetylcholine receptor. We present a family with members over four generations exhibiting sleep-related hypermotor epilepsy. Genetic testing was available for three members from three generations, and revealed two variants in the alpha-4 subunit of the nicotinic acetylcholine receptor (one of them being novel) which are likely to be disease-causing. As these mutations were identified in cis configuration (on the same allele), we do not know whether one of the variants alone or a combination of the two is responsible for the pathogenicity.