Send to

Choose Destination
Epilepsia. 2006 Oct;47(10):1732-6.

SCN1A mutation mosaicism in a family with severe myoclonic epilepsy in infancy.

Author information

Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan.



To investigate the genetic background of familial severe myoclonic epilepsy in infancy (SMEI) cases.


We performed mutation analyses of the sodium-channel gene SCN1A in two Japanese brothers with clinical features of SMEI and their parents, who had no history of febrile and epileptic seizures.


Each patient showed nucleotide changes (c.[730G>T; 735G>T; 736A>T]) in the coding exon 6 of SCN1A that led to a truncation of the channel protein. Their father showed no mutations, but their mother showed the same mutation in a subpopulation of lymphocytes.


The maternal mosaicism explains the identical SCN1A mutations in the two brothers. This highlights the importance of investigating parental mosaicism even in sporadic SMEI cases.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center