Familial pericentric inversion of chromosome 5 in a family with benign neonatal convulsions
- 1Department of Paediatrics, University of Catanzaro “Magna Graecia”, Italy
- 2Department of General Biology and Medical Genetics, University of Pavia, Italy
- 3Department of Paediatrics, 2nd University of Naples, Italy
- Correspondence to: Dr P Strisciuglio, Department of Paediatrics, Faculty of Medicine, University of Catanzaro, C/o Ospedale “A Pugliese”, Viale Pio X, 88100 Catanzaro, Italy;
We describe a family in whom a pericentric inversion of chromosome 5 segregates with benign familial neonatal convulsions (BFNC). BFNC is an autosomal dominant form of epilepsy characterised by spontaneous partial or generalised clonic convulsions beginning within the first months of life. Seizures usually disappear by the age of 6 months; intercritical electroencephalogram and subsequent psychomotor development are normal. BFNC loci have been mapped to human chromosomes 20q13.3 (BFNC1) and 8q24 (BFNC2), based on linkage analysis.1, 2 Recently, two potassium channel genes (KCNQ2 and KCNQ3), located in these two regions, were shown to be mutated in BFNC1 and BFNC2, respectively.3, 4
We report a family with BFNC and a pericentric inversion of chromosome 5 cosegregating with BFNC. Fluorescence in situ hybridisation (FISH) experiments were performed to define the breakpoints at YAC level. The linkage of BFNC to KCNQ2 and mutations in the KCNQ3 gene were excluded. This report raises the possibility of a new locus for BFNC on chromosome 5.
The proband, a male, was the second child of unrelated parents, born at 40 weeks of gestation after an uneventful pregnancy. Apgar score was 10 at one and five minutes. The parents were both 32 years old at his birth. Birth weight was 3400 g (50-75th centile), length was 51 cm (50-75th centile), head circumference was 35 cm (50-75th centile), and the clinical examination was normal except for the presence of hypotelorism. …