GABA (B) Receptor 1 Polymorphism (G1465A) Is a Marker of the Genetic Risk To Develop Mesial Temporal Lobe Epilepsy with Hippocampal Sclerosis

KAUFFMAN MARCELO; CONSALVO DAMIAN; LEVY ESTRELLA; MORDOH JOSE; KOCHEN SILVIA

San Diego, EEUU

Congreso; 58 Annual Meeting, American Academy of Neurology; 2005

AAN

Introduction: Although, the syndrome of Mesial Temporal Lobe Epilepsy with Hippocampal Sclerosis (MTLEHS) has been considered an acquired disorder, recent evidence has indicated that genetic factors are important in its genesis. The G1465A polymorphism of the GABA type B receptor gene (GABBR1) was associated with an increased risk to suffer from Temporal Lobe Epilepsy. Nevertheless, recent studies failed to find this association leading to a state of controversy about the real role of this polymorphism in the development of the disease. Objectives: To investigate the association between the G1465A polymorphism of GABBR1 and the risk to develop MTLEHS. To study the genetic association with distinctive clinical features of the disease. Methods: We have selected 52 patients with diagnosis of MTLEHS and 39 healthy controls ethnically matched with the patients. We genotypified the G1465A polymorphism of GABBR1 of the whole group by means of a PCR-RFLP assay. Results: G1465A polymorphism was more frequently observed in patients than in controls. (p=0,00013) The genotype A/G was found in 23 patients (44%) and in 3 controls (8%). To have the A/G genotype increase the risk to develop MTLEHS 9,5 times (OR 9,51; IC 95% 2.59-34.87). The patients having the A/G genotype suffered more frequently from nocturnal seizures. (p=0,01) Conclusion: The G1465A polymorphism is a risk marker for the development of MTLEHS.