Investigators from Istanbul, Turkey, studied R43Q mutations of the gamma-aminobutyric acid A receptor (GABRG2) gene, located on the long arm of chromosome 5, in 44 children with febrile seizure (FS) and 49 without. FSs were simple in 28 (63.6%) and complex in 16 (36.4%). Heterogeneous R43Q mutation of gamma-aminobutyric acid A receptor g2 subunit occurred significantly more often in the patient group (36%) than in the control group (2%); p < 0.001. The homozygous mutation carrier status was not different in the 2 groups. Family history of febrile convulsion and epilepsy was significantly higher in the study group than in controls (p < 0.01). [1]
COMMENTARY. The febrile seizure trait is inherited as a polygenic or multifactorial model or an autosomal dominant pattern with reduced penetrance [2]. Mutations of several genes have been linked to febrile seizures, including voltage-gated sodium, calcium, and potassium, and ligand-gated ion channels, nicotinic cholinergic receptor and gamma-aminobutyric acid A (GABAa) receptor. R43Q mutation of the GABAa receptor g2-subunit is involved in the cause of absence epilepsy and febrile seizure [3]. Twin studies reveal distinct genetic factors for different FS subtypes and sub-syndromes, especially FS+ [4].