Mutation information:
NumberExon/IntronNucleotide change Protein changeLocation Mutation typeConsequencesPhenotype InheritanceReference
148826c.5674C>Tp.Arg1892XC-terminalNonsenseHaploinsufficiency;pLOFSMEINASugawara T.2002
SMEIDe novo;NAFukuma G.2004
SMEIDe novoMancardi MM.2006
SMEB-ODe novoHarkin LA.2007
SMEI-HHENASakakibara T.2009
SMEINAZuberi SM.2011
SMEIDe novoNicita F.2010
SMEIDe novoWang JW.2012
SMEINAWang JW.2012
SMEINAWang JW.2012
SMEINAWang JW.2012


Functional information:
NumberNucleotide changeProtein changeLocationPhenotypeFunctional defect type Details of the major biophysical abnormalities.Reference
53c.5674C>Tp.Arg1892X (R1881X)C-Terminal SMEIpLOF Showed a drastic attenuation of the peak Na+ current, small yet detectable sodium currents.Sugawara T. 2003


[c.5674C>T] Clinical description

The first seizure of the female patient, 6-years-old, was presented with hemiclonic seizures at the age of five months. Thereafter the patent occurred other seizures including myoclonia with daily from 1 year 10 months of age , and generalized tonic clonic seizures with weekly from 1 year of age. The patient's IQ was 80. The patient's maternal aunt had convulsion. The CT and MRI was normal. The electroencephalogram analysis showed spike-wave complex and poly spike-wave complex. The MEG had no dipole clustering(Sugawara T,et al. Neurology. 2002 Apr 9;58(7): 1122-4. [11940708]).