title: Human beta2-adrenergic receptor polymorphisms: no association with essential hypertension in black or white Americans.
abstract: OBJECTIVE
  The most common polymorphisms of the human beta2-adrenergic receptor--Arg16-->Gly and Gln27-->Glu--are associated with alterations in beta2-adrenergic receptor responses, both in vitro and in vivo. beta2-Adrenergic receptor-mediated vascular responses are affected by ethnicity, blood pressure, and genotype. We tested the hypothesis that these two common beta2-adrenergic receptor genetic variants are associated with essential hypertension in black or white Americans.
  
  
  METHODS
  In a population-based case-control association study, the relationship between beta2-adrenergic receptor genotypes and hypertension was examined in 307 normotensive subjects (128 black and 179 white) and 356 hypertensive subjects (155 black and 201 white). A polymerase chain reaction-based single-stranded conformational polymorphism method with direct sequencing of the bands of interest was used to detect the two frequently occurring beta2-adrenergic receptor variants (Arg16-->Gly, Gln27-->Glu).
  
  
  RESULTS
  No significant differences in the distributions of alleles and genotypes of the tested beta2-adrenergic receptor variants were found between normotensive and hypertensive groups from either black or white Americans (all P > .05). There was a marked interethnic difference in the frequency of the Gln27-->Glu beta2-adrenergic receptor polymorphism in both normotensive and hypertensive subjects. In normotensive white subjects, the variant Glu27 allele (35.2% versus 18.0%; P < .0001) and Glu27 homozygous genotype (14.0% versus 4.7%; P < .01) were more common than in black subjects. Similarly, in hypertensive white subjects, the variant Glu27 allele (35.8% versus 18.4%; P < .0001) and the Glu27 homozygous genotype (15.9% versus 2.6%; P < .0001) were more common than in black subjects.
  
  
  CONCLUSIONS
  These data suggest that although there are marked ethnic differences in their distribution, the common genetic polymorphisms of the human beta2-adrenergic receptor gene do not cosegregate with the presence of hypertension in either black or white Americans.
authors.affiliation: Department of Medicine and Pharmacology, Vanderbilt University School of Medicine, Nashville, Tenn, USA.
authors.forename: H G
authors.initials: HG
authors.lastname: Xie
authors.forename: C M
authors.initials: CM
authors.lastname: Stein
authors.forename: R B
authors.initials: RB
authors.lastname: Kim
authors.forename: J V
authors.initials: JV
authors.lastname: Gainer
authors.forename: G
authors.initials: G
authors.lastname: Sofowora
authors.forename: V
authors.initials: V
authors.lastname: Dishy
authors.forename: N J
authors.initials: NJ
authors.lastname: Brown
authors.forename: R E
authors.initials: RE
authors.lastname: Goree
authors.forename: J L
authors.initials: JL
authors.lastname: Haines
authors.forename: A J
authors.initials: AJ
authors.lastname: Wood
mesh_terms: D000328:Adult; D000368:Aged; D044383:Black People / Q000235:genetics*; D016022:Case-Control Studies; D005260:Female; D005838:Genotype; D006801:Humans; D006973:Hypertension / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D018343:Receptors, Adrenergic, beta-2 / Q000235:genetics*; D044465:White People / Q000235:genetics*
chemical_list: D018343:Receptors, Adrenergic, beta-2