title: [Genetic study of the vasovagal syncope associated to the Arg389Gly polymorphism of the beta1 adrenergic receptor].
abstract: The purpose of this study was to evaluate the correlation between the vasovagal syncope (VVS) and the beta1 adrenergic receptor polymorphism at the 389 position. Seventy individuals with VVS were selected. DNA was extracted from peripheral blood by salting out and subjected to the amplification-restriction test. Genotype identification was made by polyacrylamide gel electrophoresis. A higher frequency in genotype and allele frequencies were found in individuals with positive tilted table test respect individuals with negative test, as well as a marked preference of the GlyGly phenotype in women. Genotype Arg389Gly was the most frequent between individuals with positive response in passive phase with respect to those in the induced phase. When the genotype was analyzed based on the hemodynamic response (VASIS) a gradient is observed in the frequency of Arg389Gly with the highest major frequency in the cardio-inhibitory response followed by the mixed response, and finally the vasodepressor response. These results suggest that the SVV has a genetic component associated with the Arg389Gly polymorphism of the adrenergic receptor. The Gly allele has a high risk association and it is maintained in the population through heterozygosis.
authors.affiliation: Departamento de Fisiología, Instituto Nacional de Cardiología Ignacio Chavez, Tlalpan, México, DF. mghp60@yahoo.com
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Hernández-Pacheco
authors.forename: Héctor
authors.initials: H
authors.lastname: Serrano
authors.forename: Manlio F
authors.initials: MF
authors.lastname: Márquez
authors.forename: Antonio G
authors.initials: AG
authors.lastname: Hermosillo
authors.forename: Nadia
authors.initials: N
authors.lastname: Pérez-Vielma
authors.forename: Arturo
authors.initials: A
authors.lastname: Sotomayor
authors.forename: Alma D
authors.initials: AD
authors.lastname: Ferreira-Vidal
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Salas-Silva
authors.forename: Manuel
authors.initials: M
authors.lastname: Cárdenas