Abstract 20047: Five Blood Pressure Loci Identified by an Updated Genome-wide Linkage Scan: Meta-analysis of the Family Blood Pressure Program
Background: The large sample size and the ethnic diversity of the final pooled dataset of the Family Blood Pressure Program (FBPP) have not been harnessed fully for identifying novel loci for blood pressure.
Methods: We performed one overall and 4 race-specific meta-analyses of blood pressure linkage results using data on 4,226 African American, 2,154 Asian, 4,229 Caucasian, and 2,435 Mexican American participants, for a total of 13,044 participants. Measured (raw) blood pressure levels and two types of antihypertensive medication adjusted blood pressure phenotypes within each of 10 subgroups defined by race and recruitment network were analyzed. We tested all markers for linkage to a quantitative trait locus (QTL). The p-values of each of the 362 common markers were combined across race-network strata using a modification of Fisher's method. We defined a QTL by logarithm of odds (LOD) score > 3 in at least one meta-analysis and LOD scores>1 in at least 2 race-network strata.
Results: In all, five QTLs were detected on chromosomes 6p22.3, 8q23.1, 20q13.12, 21q21.1, and 21q21.3. The locus for diastolic blood pressure (overall meta LOD score=3.12) on chromosome 8q23.1 was also supported by Asian-, Caucasian-, and Mexican-American-specific meta-analyses each with LOD scores >1. Candidate genes in this region include YWHAZ, ANGPT1, ZFPM2, and OXR1.
Conclusions: We conclude that the new QTLs reported justify investigations of candidate genes in these QTL regions. These QTLs may harbor genes containing less common variants with large effects on blood pressure levels and hypertension. Information about these QTLs may help support results for genome-wide association study (GWAS) single nucleotide polymorphisms (SNPs) that fall in these QTL regions but fail to achieve the genome-wide significance.
- © 2010 by American Heart Association, Inc.