Recapitulation of genome-wide association studies on pulse pressure and mean arterial pressure in the Korean population

Efficacy of Immediate Antihypertensive Treatment in Patients With Acute Ischemic Stroke With Different Blood Pressure Genetic Variants

BACKGROUND

It remains unclear whether blood pressure (BP) genetic variants could modify the efficacy of immediate antihypertensive treatment after acute ischemic stroke. We conducted a secondary analysis of the CATIS (China Antihypertensive Trial in Acute Ischemic Stroke) to investigate the effect of early antihypertensive treatment on clinical outcomes among patients with acute ischemic stroke according to 5 BP-associated genetic variants.

METHODS

The CATIS randomized 4071 patients with acute ischemic stroke with elevated systolic BP to receive antihypertensive treatment or discontinue all antihypertensive agents during hospitalization. Randomization was conducted centrally and was stratified by participating hospitals and use of antihypertensive medications. Five BP-associated single nucleotide polymorphisms (rs16849225, rs17030613, rs1173766, rs6825911, and rs35444 in FIGN-GRB14, ST7L-CAPZA1, NPR3, ENPEP, and near TBX3, respectively) were genotyped among 2590 patients. The primary outcome was a combination of death and major disability at 14 days or hospital discharge. A weighted BP genetic risk score was constructed by the 5 single nucleotide polymorphisms.

RESULTS

At 14 days or hospital discharge, the primary outcome was not significantly different between antihypertensive treatment and control groups based on genotype subgroups for all 5 single nucleotide polymorphisms (all P>0.05 for interaction). In addition, the BP genetic risk score did not modify the effect of antihypertensive treatment. The odds ratios (95% CIs) for the primary outcome were 0.95 (0.71-1.26), 1.08 (0.80-1.44), and 0.91 (0.69-1.22) in patients with low, intermediate, and high BP genetic risk score, respectively (P=0.88 for interaction).

CONCLUSIONS

Early antihypertensive treatment had a neutral effect on clinical outcomes among patients with acute ischemic stroke according to 5 BP-associated genetic variants.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01840072.

A unified mapping framework of multifaceted pharmacodynamic responses to hypertension interventions

The personalized therapy for hypertension needs comprehensive knowledge about how blood pressures (BPs; systolic and diastolic) and their pulsatile and steady components are controlled by genetic factors. Here, we propose a unified pharmacodynamic (PD) functional mapping framework for identifying specific quantitative trait loci (QTLs) that mediate multivariate response-dose curves of BP. This framework can characterize how QTLs govern pulsatile and steady components through jointly regulating systolic and diastolic pressures. The model can quantify the genetic effects of individual QTLs on maximal drug effect, the maximal rate of drug response, and the dose window of maximal drug response. This unified mapping framework provides a tool for identifying pharmacological genes potentially useful to design the right medication and right dose for patients.

A Review of the Genetics of Hypertension with a Focus on Gene-Environment Interactions

PURPOSE OF REVIEW

Here, we discuss the interpretation and modeling of gene-environment interactions in hypertension-related phenotypes, with a focus on the necessary assumptions and possible challenges.

RECENT FINDINGS

Recently, small cohort studies have discovered several novel genetic variants associated with hypertension-related phenotypes through modeling gene-environment interactions. Several consortia-based meta-analytic efforts have uncovered many novel genetic variants in hypertension without modeling interaction terms, giving promise to future meta-analytic efforts that incorporate gene-environment interactions. Heritability studies and genome-wide association studies have established that hypertension, a prevalent cardiovascular disease, has a genetic component that may be modulated by the environment (such as lifestyle factors). This review includes a discussion of known genetic associations for hypertension/blood pressure, including those resulting from the incorporation of gene-environmental interaction modeling.

International Genome-Wide Association Study Consortium Identifies Novel Loci Associated With Blood Pressure in Children and Adolescents

BACKGROUND

Our aim was to identify genetic variants associated with blood pressure (BP) in childhood and adolescence.

METHODS AND RESULTS

Genome-wide association study data from participating European ancestry cohorts of the Early Genetics and Lifecourse Epidemiology (EAGLE) Consortium was meta-analyzed across 3 epochs; prepuberty (4-7 years), puberty (8-12 years), and postpuberty (13-20 years). Two novel loci were identified as having genome-wide associations with systolic BP across specific age epochs: rs1563894 (ITGA11, located in active H3K27Ac mark and transcription factor chromatin immunoprecipitation and 5'-C-phosphate-G-3' methylation site) during prepuberty (P=2.86×10(-8)) and rs872256 during puberty (P=8.67×10(-9)). Several single-nucleotide polymorphism clusters were also associated with childhood BP at P<5×10(-3). Using a P value threshold of <5×10(-3), we found some overlap in variants across the different age epochs within our study and between several single-nucleotide polymorphisms in any of the 3 epochs and adult BP-related single-nucleotide polymorphisms.

CONCLUSIONS

Our results suggest that genetic determinants of BP act from childhood, develop over the lifecourse, and show some evidence of age-specific effects.

Gene set analyses of genome-wide association studies on 49 quantitative traits measured in a single genetic epidemiology dataset

Gene set analysis is a powerful tool for interpreting a genome-wide association study result and is gaining popularity these days. Comparison of the gene sets obtained for a variety of traits measured from a single genetic epidemiology dataset may give insights into the biological mechanisms underlying these traits. Based on the previously published single nucleotide polymorphism (SNP) genotype data on 8,842 individuals enrolled in the Korea Association Resource project, we performed a series of systematic genome-wide association analyses for 49 quantitative traits of basic epidemiological, anthropometric, or blood chemistry parameters. Each analysis result was subjected to subsequent gene set analyses based on Gene Ontology (GO) terms using gene set analysis software, GSA-SNP, identifying a set of GO terms significantly associated to each trait (pcorr < 0.05). Pairwise comparison of the traits in terms of the semantic similarity in their GO sets revealed surprising cases where phenotypically uncorrelated traits showed high similarity in terms of biological pathways. For example, the pH level was related to 7 other traits that showed low phenotypic correlations with it. A literature survey implies that these traits may be regulated partly by common pathways that involve neuronal or nerve systems.