title: The 894T allele of endothelial nitric oxide synthase gene is related to left ventricular mass in African Americans with high-normal blood pressure.
abstract: OBJECTIVE
  The 894T allele in exon 7 of the endothelial nitric oxide synthase (eNOS) gene has been inconsistently associated with hypertension in different racial groups. Because high-normal blood pressure (BP) confers an increased risk for the development of hypertension and other cardiovascular disorders, including left ventricular hypertrophy (LVH), we tested the hypothesis that the allelic variation (894T) in the eNOS gene would directly correlate with alterations in LV mass (LVM) in individuals with high-normal BP.
  
  
  METHODS
  Genotype distribution of G894T was compared between 20 African Americans (10 females/10 males) with high-normal BP (systolic BP of 130-139 and/or diastolic BP of 85-89 mmHg) and 64 counterparts (37 females/27 males) with normal BP (<130/85 mmHg). Echocardiographic LVM was calculated (Devereux formula) and indexed to body surface area to define the presence of LVH (LVMI >134/110 g/m2 for men/women).
  
  
  RESULTS
  For the entire group, the 894T allelic frequencies (15, 48%) and G894T genotype distributions were consistent with the Hardy-Weinberg equilibrium expectations (estimated disequilibrium coefficient = 0.0118, P=0.40). LVMI was significantly higher in homozygous carriers (TT) of the rare 894T allele (n = 3 females/0 males) than in heterozygous GT (n = 13 females/7 males) and individuals bearing the GG (n=34 females/27 males) variant (124 +/- 70 vs. 82 +/- 24 and 82 +/- 19 g/m2, respectively, P < 0.05). The observed relationship between eNOS 894T allele and LVMI was restricted to individuals with high-normal BP (r = 0.94, P = 0.03) but not in those with normal BP (r = 0.39, P =0.64), by analysis of variance (ANOVA) after adjusting for age, gender, body mass index, smoking and systolic BP.
  
  
  CONCLUSIONS
  These findings, not previously described, provide important preliminary evidence to suggest an increased susceptibility to LVH in African Americans who carry the 894T variant of the eNOS gene and have high-normal blood pressure.
authors.affiliation: Division of Cardiology, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, GA 30310, USA. lapbulr@msm.edu
authors.forename: Rigobert
authors.initials: R
authors.lastname: Lapu-Bula
authors.forename: Alexander
authors.initials: A
authors.lastname: Quarshie
authors.forename: Deborah
authors.initials: D
authors.lastname: Lyn
authors.forename: Adefisayo
authors.initials: A
authors.lastname: Oduwole
authors.forename: Cheryl
authors.initials: C
authors.lastname: Pack
authors.forename: Jan
authors.initials: J
authors.lastname: Morgan
authors.forename: Sunday
authors.initials: S
authors.lastname: Nkemdiche
authors.forename: Priscilla
authors.initials: P
authors.lastname: Igho-Pemu
authors.forename: Anekwe
authors.initials: A
authors.lastname: Onwuanyi
authors.forename: Rongling
authors.initials: R
authors.lastname: Li
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Ofili
mesh_terms: D000328:Adult; D001741:Black or African American / Q000235:genetics*; D000483:Alleles; D001794:Blood Pressure; D003326:Coronary Circulation / Q000235:genetics; D004730:Endothelium, Vascular; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D006973:Hypertension / Q000208:ethnology* / Q000235:genetics*; D017379:Hypertrophy, Left Ventricular / Q000208:ethnology* / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D019001:Nitric Oxide Synthase / Q000235:genetics*; D052250:Nitric Oxide Synthase Type III; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors
chemical_list: C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III