Objective To investigate the gene mutation of families with familial Dravet syndrome(DS). Methods The peripheral blood DNA samples were extracted from 90 children with DS and their families by PCR amplification and gene sequencing. PCR-DNA direct sequencing and multiple junction dependent probe amplification were used to screen the SCN1A gene mutation, and the capture sequencing epileptic gene detection kit was used to screen the families without SCN1A gene mutation. Results SCN1A gene mutation was found in 62 of 90 children, with the mutation rate of 68.89%, including 29 children with missense mutation, 26 with truncated mutation, 5 with shear site mutation and 2 with SCN1A gene fragment repetition or deletion. Five families were found SCN1A gene mutations, 3 of which were maternal SCN1A genetic heterozygous mutation, and their mothers were clinically phenotyped with DS or febrile convulsion, while the other 2 families were found SCN1A mutant chimeras from one of parents and normal clinical phenotype of both parents. Conclusion The familial DS is mostly caused by SCN1A gene mutation.
Journal of Chinese Practical Diagnosis and Therapy