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Genes of Hypertension in African Americans

This study has been completed.
National Heart, Lung, and Blood Institute (NHLBI)
Information provided by (Responsible Party):
Theodore Kotchen, MD, Medical College of Wisconsin Identifier:
First received: June 30, 2003
Last updated: April 22, 2014
Last verified: April 2014
To identify genes contributing to hypertension in African Americans by focusing on the physiological pathways that determine arterial pressure.

Cardiovascular Diseases
Heart Diseases

Study Type: Observational
Study Design: Observational Model: Case Control
Time Perspective: Cross-Sectional
Official Title: Genes of Hypertension in African Americans

Resource links provided by NLM:

Further study details as provided by Medical College of Wisconsin:

Primary Outcome Measures:
  • genes of hypertension in African Americans [ Time Frame: One time data collection ]
    There is no intervention

Biospecimen Retention:   Samples With DNA
Blood cells and DNA

Enrollment: 5000
Study Start Date: December 2002
Study Completion Date: July 2008
Primary Completion Date: July 2008 (Final data collection date for primary outcome measure)
Detailed Description:


Since the mid 1990s, the investigators have extensively characterized African Americans for phenotypes related to cardiovascular and renal function. Based on recently completed genome scans, they have identified several chromosomal regions likely to contain genes influencing hypertension-related phenotypes in hypertensive, African American sib pairs. For several phenotypes, overlapping QTLs have also been identified in related studies in a genetically isolated French Canadian population and/or in homologous chromosomal regions in the F2 cross of Dahl-salt sensitive x normotensive Brown Norway rats.


The investigators will extensively phenotype 500 hypertensive and 500 normotensive African American subjects to conduct a genetic association study, using a single nucleotide polymorphism (SNP) genomic scan approach. To achieve a clear separation of blood pressures from hypertensive subjects, normotensive subjects will be selected from the lower third of the population-based blood pressure distribution. Hypertensive (BMI), and age. Inclusion of phenotypes is based on their relevance to the pathophysiology of hypertension and prior evidence of "heritability." Candidate genes for SNP analysis will be selected within chromosomal regions of two quantitative trait loci (QTLs) that they have previously demonstrated to be linked to hypertension-related phenotypes--a QTL for body mass index on chromosome 1 and a QTL for microalbuminuria on chromosome 18. SNP analyses will be carried out in 15 percent of the genes within each of these QTLs, and genes will be selected on the basis of their relevance to hypertension, including documented sequence conservation for blood pressure related QTLs with rat or mouse. The final goal of the project is to determine if distinct clusters of blood pressure related phenotypes can be identified that will permit stratification of hypertensive individuals into distinct subgroups to facilitate the analysis of the genetic determinants of hypertension and/or provide mechanistic leads to genes contributing to these traits.


Ages Eligible for Study:   18 Years to 75 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
African Americans
African Americans, age 18-75 years
  Contacts and Locations
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Please refer to this study by its identifier: NCT00063505

Sponsors and Collaborators
Medical College of Wisconsin
National Heart, Lung, and Blood Institute (NHLBI)
Principal Investigator: Theodore Kotchen Medical College of Wisconsin
  More Information

Responsible Party: Theodore Kotchen, MD, Professor, Asssociate Dean for Clinical Research, Medical College of Wisconsin Identifier: NCT00063505     History of Changes
Other Study ID Numbers: 1216
R01HL070111 ( US NIH Grant/Contract Award Number )
Study First Received: June 30, 2003
Last Updated: April 22, 2014

Additional relevant MeSH terms:
Cardiovascular Diseases
Heart Diseases
Vascular Diseases processed this record on April 25, 2017