BENIGN CHILDHOOD EPILEPSY WITH CENTROTEMPORAL SPIKES AND ELECTROENCEPHALOGRAPHY TRAIT ARE NOT LINKED TO EBN1 AND EBN2 OF BENIGN NEONATAL FAMILIAL CONVULSIONS

Purpose: The electroencephalographic hallmark of benign childhood epil epsy with centrotemporal spikes (BECTS, or rolandic epilepsy) are char acteristically shaped centrotemporal spikes and sharp waves (CTS). Thi s EEG trait, but not BECTS itself, has been reported to follow an auto somal dominant mode of inheritance with incomplete penetrance and age dependence. CTS therefore represents a neurobiologic marker for the in creased risk of developing BECTS. Benign neonatal familial convulsions (BNFC) like BECTS is an idiopathic age-dependent epilepsy with a beni gn course. Observations of benign neonatal seizures and BECTS in the s ame individual are well documented. Neonatal seizures with benign cour se were found in increased numbers in a series of CTS carriers. Two ge netic loci, EBN1 and EBN2, have been mapped in families with BNFC, mak ing these two loci strong candidates for the CTS trait underlying BECT S. The aim of this study was to determine whether these two epilepsy s yndromes are allelic disorders. Methods: Linkage analysis was performe d in 12 families with probands with BECTS and one or more relatives wi th CTS in the EEG with or without BECTS by using polymorphic DNA marke rs. Results: Assuming an autosomal mode of inheritance with penetrance s of 0.9 and 0.45, respectively, both loci were consistently excluded. Conclusions: The CTS trait and EBN1 and EBN2 segregate independently, BECTS and BNFC therefore appear to be genetically distinct entities. Benign neonatal seizures may be a underrecognized symptom of the CTS t rait itself.