The nicotinic receptor β2 subunit is mutant in nocturnal frontal lobe epilepsy

Abstract
Clustered attacks of epileptic episodes originating from the frontal lobe during sleep are the main symptoms of autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE, MIM 600513). Despite the clinical homogeneity, three forms of ADNFLE have been associated with chromosomes 20 (ENFL1; ref. 1), 15 (ENFL2; ref. 2) and 1 (ENFL3; ref. 3). Mutations of the gene encoding the neuronal nicotinic acetylcholine receptor α4 subunit (CHRNA4 ) have been found in ADNFLE-ENFL1 families4,5,6, but these mutations account for only a small proportion of ADNFLE cases7. The newly identified locus associated with ENFL3 harbours several candidate genes, including CHRNB2 (ref. 8), whose gene product, the β2 nicotinic acetylcholine receptor (nAChR) subunit, co-assembles with the α4 nAChR subunit to form the active receptor9.