Mosaic SCN1A mutation in a family with partial epilepsy with febrile seizures plus / 中华神经科杂志

ABSTRACT

Objective To study the SCN1A gene in a family with partial epilepsy with febrile seizures plus ( PEFS+ ) and its characteristics of inheritance. Methods The clinical features of the 2 patients and their father were summarized. All 26 exons of SCN1A gene were screened with denaturing high performance liquid chromatography (DHPLC), and direct sequence analysis was pedormed on those with abnormal elution peak. Pyrosequencing was subsequently performed in those without abnormality in direct sequence analysis. Results The proband and his sister had the phenotype of PEFS+ . The same heterozygous mutations (AS768G) on exon 26 which caused the related amino acid change (Q1923R) were found among them. Their father had frequent febrile seizures (FS) in childhood, and seizures stopped spontaneously. No abnormality was found in direct sequence but mosaic mutation in the same site was discovered with pyrosequencing (mutation quantity was 25% ). Conclusions The mutatin of SCN1A could cause partial epilepsy. PEFS+ could be inherited, the relatives carrying the affected gene may have mild clinical symptoms, possibly resulting from the low concentration of the mutated gene due to mosaic mutation.