{'fraction_non_alphanumeric': 0.018893387314439947, 'fraction_numerical': 0.01349527665317139, 'mean_word_length': 5.502923976608187, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Association Analysis of γ2 Subunit of γ-aminobutyric Acid (GABA) Type A Receptor and Voltage-gated Sodium Channel Type II α-polypeptide Gene Mutation in Southern Chinese Children With Febrile Seizures

family epilepsies share important clinical features, they may share a common genetic etiology. The chromosomal locus 2q24, in which generalized epilepsy with febrile seizures plus (GEFS+) has been mapped, harbors the SCN2A gene. An association between the SCN2A R19K polymorphism, R188W mutation, and febrile seizures has been detected. R188W mutation of the SCN2A gene occurred on a highly conserved residue among voltage-gated Na+ channels. A channel harboring the mutation shows abnormal electrophysiological properties that may underlie the neuronal hyperexcitability that triggers seizure activity. R188W mutation of the SCN2A gene with channel dysfunction was recently identified in a patient with febrile seizures and afebrile seizures. Wholecell patch clamp recordings on human embryonic kidney cells expressing a rat wild type and the corresponding mutant channels showed that the mutant channel inactivated more slowly than the wild type, whereas the conductance of the Na+ channel was not affected. Prolonged residence in the open state of the R188W mutant channel may augment Na+ influx and thereby underlie the neuronal hyperexcitability that induces seizure activity. These findings strongly suggested that the R188W mutation as the genetic defect was responsible for convulsive disorders. Febrile seizures, the most common form of convulsions, are characterized by a short duration of seizures during rapidly rising fever. Although the pathogenesis of febrile seizures remains obscure, it has long been known that approximately 30% of children with febrile seizures have a family history of them. Febrile seizures show a genetic predisposition and are usually regarded as having a polygenic basis. Some forms of family epilepsy may initially present as febrile seizures, and several of these disorders are caused by channelopathies such as in the neuronal sodium channels type II αpolypeptide (SCN2A) and γ-aminobutyric acid type A (GABAA) receptors. 3,4 Because febrile seizures and these Original Article