No evidence of linkage to 6p markers in Spanish families with juvenile myoclonic epilepsy

Juvenile myoclonic epilepsy (JME) is a common subtype of hereditary generalized epilepsy with an uncertain pattern of inheritance. Different studies in multiple families have provided evidence for and against linkage of the disease to chromosome 6p. We performed linkage analysis using microsatellite markers from 6p (D6S109, D6S248, D6S291, D6S426, D6S272, D6S466, D6S294, D6S257) and from centromeric 6q region (D6S402) in seven small families of Spanish origin. The highest LOD scores were obtained under an autosomal dominant inheritance model with a penetrance of 70% but a significant positive LOD score (Z > 3) was not reached. LOD scores < -2 were obtained at different markers in three of our families. These results support the concept of genetic heterogeneity in the disease. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.