Abstract MP086: Association Between the Angiotensin-Converting Enzyme-2 Gene and Blood Pressure in a Cohort of Canadian Adolescents
Background: The Angiotensin-Converting Enzyme-2 (ACE2) gene, located on chromosome X, is believed to be implicated in blood pressure (BP) regulation. However the few studies that have assessed this association have yielded mixed results. We examined the association between BP and ACE2 single nucleotide polymorphisms (SNPs) in a population-based cohort of adolescents, thereby minimizing confounding by treatment for hypertension and other chronic diseases.
Methods: Participants were 852 of 1293 adolescents from the Nicotine Dependence In Teens (NDIT) cohort study. Participants provided a blood sample for DNA, and BP was measured on the right arm at rest, in the sitting position, by trained, certified technicians using an automated oscillometric device at age 12, 15 and 17 years. Instruments were calibrated against mercury sphygmomanometer before each data collection. Systolic (SBP) and diastolic blood pressure (DBP) were measured 3 times at 1-minute intervals, and the mean was used for analysis. Four SNPs (rs2074192, rs233575, rs2158083, rs1978124) in the ACE2 gene were genotyped. The relationship between ACE2 SNPs and each of SBP and DBP was examined using linear growth models adjusted for height and ethnicity, and stratified by sex.
Results: Mean age at baseline was 12.7 years; 47.8% of participants were male (n=407 of 852). All SNPs were in Hardy-Weinberg equilibrium (p>0.05), and three of the four SNPs were in linkage disequilibrium (rs233575 and rs2158083 r2: 0.71; rs1978124 and rs233575 r2: 0.36; rs2158083 and rs1978124 r2: 0.52) with each other. SNP rs2074192 was in low linkage disequilibrium with these 3 SNPs (r2 <0.3). Compared to boys carrying the G allele, SBP in boys carrying the A allele of SNP rs2074192 was 2.45 mmHg lower (CI: 0.20-4.70, p=0.0350); DBP was 1.67 mmHg lower (CI: 0.47-2.87, p=0.0067). SNPs rs233575, rs2158083, and rs1978124 were not significantly associated with SBP or DBP in boys. None of the four SNPs were associated with SBP or DBP in girls.
Conclusion: Because elevated BP tracks from childhood to adulthood, the ACE2 gene could represent a new therapeutic target in boys to prevent elevated BP. Association between this gene and BP and potential for prevention should be further investigated.
- © 2012 by American Heart Association, Inc.