Mutation information:
NumberExon/IntronNucleotide change Protein changeLocation Mutation typeConsequencesPhenotype InheritanceReference
168826c.5555T>Cp.Met1852Thr C-terminal Missense N→P/O(81); pLOFSMEI Familial(Paternal,FS+),P=5/5Annesi G.2003
GEFS+Pyrosequencing:26%;mosaic(Paternal,asympt),Xu X.2015

Functional information:
NumberNucleotide changeProtein changeLocationPhenotypeFunctional defect type Details of the major biophysical abnormalities.Reference
51c.5555T>Cp.Met1852Thr(M1852T)C-terminalSMEI fpLOF Reduced current density that could be partially rescued, with trafficking defect involved.Rusconi R.2007

Inheritance information:
NumberNucleotide changeProtein changeMutation type Proband's phenotype1st transmitter's phenotype Mosaic Affected generationsPenetranceReference
166c.5555T>Cp.Met1852Thr(C-terminal)MissenseSMEIFS+(Paternal) 25/5Annesi G.2003

[c.5555T>C] Clinical description

The mutation is a heterozygous point mutation, which was detected in both affected members of family, but not in their mother, who was unaffected. Notably, one of the affected members of this family is the one with SMEI. His sister, who carried the same mutation, had a milder phenotype of GEFS+, whereas the father, who had died at the time of the study, had FS+(Annesi G,et al. Epilepsia, 2003, 44(9):1257–1258. [12919402]).