Molecular Epidemiology of Essential Hypertension
Condition: Cardiovascular Diseases; Heart Diseases; Coronary Disease; Hypertension
MeSH terms: Hypertension; Cardiovascular Diseases; Heart Diseases; Coronary Disease
Study type: Observational

Summary: 
      To localize individual genes, called blood pressure quantitative trait genes [BPQTGs], which
      influence blood pressure levels in the population-at- large, and to determine if these genes
      are able to predict the occurrence of essential hypertension or coronary artery disease.
    

Detailed description: 
      BACKGROUND:

      Essential hypertension reaches epidemic proportions among adults and is a significant risk
      factor for premature coronary artery disease [CAD] and stroke. The research to localize
      BPQTGs represents an initial step toward applying DNA information to early identification of
      at-risk individuals and understanding the complex relationships among blood pressure,
      essential hypertension, and coronary artery disease.

      DESIGN NARRATIVE:

      The study has four aims. Aim 1 uses robust sibling pair linkage methods, parental marker
      data, and office blood pressure levels measured on 1,376 full sibling pairs to localize
      BPQTGs to regions of the human genome marked by highly polymorphic tandem repeat loci in or
      very near to 59 genes involved in blood pressure regulation. These genes were selected based
      on their involvement in the renin/angiotensin system, ion transport, cardiac physiology,
      biometabolism of neurotransmitters, or carbohydrate and lipid metabolism. At each gene, a
      highly polymorphic tandem repeat marker locus has already been identified. Aim 2 uses methods
      of association analysis for related individuals and office blood pressure levels measured on
      587 full sibships to localize BPQTGs to regions of the human genome marked by the 59
      candidate BPQTGs. Aim 3 determines if variation in these BPQTGs improves the ability to
      predict differences in blood pressure levels in a sample of 1,166 unrelated normotensive
      adults or essential hypertension status in a sample of 1,160 unrelated grandparents beyond
      that provided by established predictors. Aim 4 determines if variation in these BPQTGs
      improves the ability to predict symptomatic or asymptomatic coronary artery disease status
      beyond that provided by established predictors including blood pressure and essential
      hypertension. Aims 3 and 4 also ask whether the predictive relationship of the traditional
      risk factors to blood pressure, essential hypertension, or coronary artery disease is
      different among genotypes at these BPQTGs.

      The study was renewed in FY 1999 to continue data analysis.
    

Observational model: Family-Based
Time perspective: Retrospective
Sampling method: Probability Sample
Study population: 
        Members of 573 randomly-ascertained multigeneration pedigrees from the Rochester Family
        Heart Study
      
Biospecimen description: 
      This project will make use of previously collected DNA and clinical data from members of 573
      randomly-ascertained multigeneration pedigrees from the Rochester Family Heart Study.