Genetic dissection of hypertension (HTN) and co-morbidities, carried out largely through traditional linkage analysis, has mostly been unsuccessful to date in identifying specific genetic variants. Motivated by existing evidence that some of the genetic effects are modulated by age and obesity, the investigators have developed appropriate new methods for gene discovery. This revised application addresses the hypothesis that gene-age and gene-obesity interactions are important in the genotype-phenotype correlations. The growing obesity epidemic world-wide makes it particularly important to investigate whether and to what extent obesity modulates genetic effects on HTN and blood pressure. The primary goal of the proposed developmental research is to understand how genes interact with age and obesity in producing blood pressure and HTN. The research will be carried out using the phenotypic and genotypic data previously collected in the large Family Blood Pressure Program (FBPP) that includes African American, White and Hispanic hypertensive families from 3 Networks, incorporating 11,040 individuals. Our proposed study is highly cost effective because it takes full advantage of these extraordinary resources which exist already. The proposed research will investigate the role of age variation in genetic effects and how obesity modulates genetic effects in HTN and blood pressure by performing linkage analysis using our recent method which has been shown to be very powerful. This study is unique in that ethnic differences in the modulation effects also can be investigated. The current exploratory grant is based on novel modeling concepts and one of the largest samples ever collected on HTN. Identifying appropriate ethnic-specific ages (and the critical obesity levels) when genetic variants exert the most influence opens up new avenues of research in terms of finding specific genetic variants and the optimal timing of interventions as well as the development of new pharmaceutical treatments targeted toward the idiosyncrasies of age, obesity and ethnicity. From a public health perspective, individuals with a modifiable genetic risk of HTN could be identified prior to disease development, and effective and appropriate lifestyle modifications and/or pharmaceutical treatments could be implemented for primary prevention.

Public Health Relevance

Risk for hypertension is not constant across age or obesity levels or between ethnic groups;it is reasonable to assume that genetic effects also are not static. Our novel linkage approach incorporating ethnic-specific gene- age and obesity-age interactions as modulators in hypertensive siblings has the potential to identify individuals with modifiable genetic risk, determine optimal timing of intervention and develop targeted drug treatments.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21HL095054-01A1
Application #
7738843
Study Section
Genomics, Computational Biology and Technology Study Section (GCAT)
Program Officer
Jaquish, Cashell E
Project Start
2009-09-30
Project End
2011-07-31
Budget Start
2009-09-30
Budget End
2010-07-31
Support Year
1
Fiscal Year
2009
Total Cost
$152,000
Indirect Cost
Name
Washington University
Department
Biostatistics & Other Math Sci
Type
Schools of Medicine
DUNS #
068552207
City
Saint Louis
State
MO
Country
United States
Zip Code
63130
Simino, Jeannette; Kume, Rezart; Kraja, Aldi T et al. (2014) Linkage analysis incorporating gene-age interactions identifies seven novel lipid loci: the Family Blood Pressure Program. Atherosclerosis 235:84-93
Simino, Jeannette; Shi, Gang; Weder, Alan et al. (2014) Body mass index modulates blood pressure heritability: the Family Blood Pressure Program. Am J Hypertens 27:610-9
Simino, Jeannette; Shi, Gang; Arnett, Donna et al. (2011) Variants on chromosome 6p22.3 associated with blood pressure in the HyperGEN study: follow-up of FBPP quantitative trait loci. Am J Hypertens 24:1227-33
Simino, Jeannette; Shi, Gang; Kume, Rezart et al. (2011) Five blood pressure loci identified by an updated genome-wide linkage scan: meta-analysis of the Family Blood Pressure Program. Am J Hypertens 24:347-54
Shi, Gang; Rao, D C (2011) Optimum designs for next-generation sequencing to discover rare variants for common complex disease. Genet Epidemiol 35:572-9