|Number||Exon/Intron||Nucleotide change||Protein change||Location||Mutation type||Consequences||Phenotype||Inheritance||Reference|
|676||15||c.2593C>G||p.Arg865Gly||DIIS4||Missense||P/﹢→N (125); G-LOF||SMEI||NA||Volkers L.2011|
|Number||Nucleotide change||Protein change||Location||Phenotype||Functional defect type||Details of the major biophysical abnormalities.||Reference|
|15||c.2593C>G||p.Arg865Gly(R865G)||DIIS4||SMEI||G-LOF||A large increase in persistent current, and a hyperpolarized shift in the voltage dependence of activation in combination with the unaltered voltage dependence of inactivation; slower recovery from inactivation.||Volkers L.2011|
|[c.2593C>G] Clinical description|
The novel R865G mutation was detected in a boy who had right-sided hemiconvulsions with postictal hemiparesis since the age of nine months. He also experienced myoclonic jerks and complex partial seizures. His EEGs showed a near normal background pattern with isolated sharps and sharp waves in both hemispheres. He was diagnosed with DS. Magnetic resonance brain imaging was normal. At the age of 60 months, he was deemed to have a severe developmental delay with a developmental age of 29 months. After addition of levetiracetam to valproate and lamotrigine at the age of 6.5 years he is seizure free till to date.His family history was negative for febrile convulsions and epilepsy. His parents are consanguineous. DNA analysis of the parents was not available(Volkers L,et al. Eur J Neurosci. 2011 Oct;34(8): 1268-75. ).
Copyright ©2014 Institute of Neuroscience and The Second Affiliated Hospital of Guangzhou Medical University
Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China
Collaborative Innovation Center for Neurogenetics and Channelopathies, Guangzhou 510260, China.