Blood Pressure Traits Research Articles

Heritability of blood pressure traits in diverse populations: a systematic review and meta-analysis.

To understand the genetic architecture and make inferences about transmissible resemblance of systolic and diastolic blood pressure (SBP and DBP) traits in relatives, the polygenic effect of individual alleles in terms of narrow heritability (h2) is usually assessed. The heritability estimates for BP traits are population specific parameters with a wide range in different studies (6-68%), and there is no comprehensive evidence comparing its source(s) of heterogeneity. To fill the gap, this systematic review and meta-analysis study was carried out. Using MeSH terms, 647 records were detected through searching, "Pubmed," "Ebsco," "Web of Science," and "Scopus" databases. From these, 24 relevant full-text articles with 47 comparisons for final quantitative meta-analysis were included in our review over the five continents. The additive genetic effects of both traits showed a widespread distribution (h2SBP: 17-52%, h2DBP:19-41%). Different categories of transmissible resemblance for BP traits were explained by ethnicity; higher heritability was estimated in Europeans and Mexican Americans, while lower heritability was seen in the Middle Eastern, Asians, Africans, Latinos, Hispanics, and American Indians. Low heterogeneity of polygenic effects was seen for both traits in subgroups of the Middle East, Asians, Africans, and Latinos, Hispanics, American Indians. However, there was a substantial heterogeneity of h2 within European and Mexican American studies. Neither pedigree type nor other covariates explained the variance of additive genetic effects of BP traits in different ethnicities.

Intra‐arterial blood pressure traits during and after heavy resistance exercise in healthy males

Intra‐arterial blood pressure traits during and after heavy resistance exercise in healthy males

Association between homocysteine level and blood pressure traits among Tibetans: A cross-sectional study in China.

Studies on hypertension (HTN) in Tibetans who live in high altitude areas are less and whether total homocysteine level (tHcy) is associated with blood pressure (BP) levels or HTN status in Tibetans is unknown.A total of 1486 Tibetans with complete information from a cross-sectional survey conducted in Lhasa Chengguan County of Tibet were included in this study. Demographic data, self-reported history of disease, and life styles were collected using a questionnaire. Blood tHcy, creatinine, fasting plasma-glucose, total cholesterol, triglycerides, and BP were measured with equipment.The median tHcy level of the whole population was 14.60 (13.17–16.50) μmol/L, and the prevalence of HTN was 26.99%. Regression models, adjusted for possible covariates, showed that an average increase of 1 lnHcy (log transformation of tHcy level) was associated with an increase of 3.78 mmHg of systolic BP (SBP, P = .011) and 3.02 mmHg of diastolic BP (DBP, P = .003). The prevalence of HTN, levels of SBP and DBP in the third (OR for HTN: 1.60, P = .026; β for SBP: 3.41, P = .004; β for DBP: 2.57, P = .002) and fourth (OR for HTN: 2.19, P < .001; β for SBP: 5.08, P < .001; β for DBP: 3.09, P < .001) quartile of tHcy level were higher than those in the first quartile.THcy is associated with BP levels and HTN status among Tibetans. Both HTN management and tHcy level should be paid more attention in Tibetans.

Meta-Qtest: meta-analysis of quadratic test for rare variants

BackgroundIn genome-wide association studies (GWASs), meta-analysis has been widely used to improve statistical power by combining the results of different studies. Meta-analysis can detect phenotype associated variants that are failed to be detected in single studies. Especially, in biomedical sciences, meta-analysis is often necessary not only for improving statistical power, but also for reducing unavoidable limitation in data collection. As next-generation sequencing (NGS) technology has been developed, meta-analysis of rare variants is proceeding briskly along with meta-analysis of common variants in GWASs. However, meta-analysis on a single variant that is commonly used in common variant association test is improper for rare variants. A sparse signal of rare variant undermines the association signal and its large number causes multiple testing problem. To over-come these problems, we propose a meta-analysis method at the gene-level rather than variant level.ResultsAmong many methods that have been developed, we used the unified quadratic tests (Q-tests); Q-test is more powerful than or as powerful as other tests such as Sequence Kernel Association Tests (SKAT). Since there are three different versions of Q-test (QTest1, QTest2, QTest3), each assumes different relationships among multiple rare variants, we extended them into meta-study accordingly. For meta-analysis, we consider two types of approaches, the one is to combine regression coefficients and the other is to combine test statistics from each single study. We extend the Q-test for meta-analysis, proposing Meta Quadratic Test (Meta-Qtest). Meta Q-test avoids the limitations of MetaSKAT. It does not only consider genetic heterogeneity among studies as MetaSKAT but also reflects diverse real situations; since we extend three different Q-tests into meta-analysis respectively, flexible Meta Q-test suggests way to deal with gene-level rare variant meta-analysis efficiently From the results of real data analysis of blood pressure trait, our meta-analysis could successfully discovered genes, KCNA5 and CABIN1 that are already well known for relevance with hypertension disease and they are not detected in MetaSKAT.ConclusionAs exemplified by an application to T2D Genes projects data set, Meta-Qtest more effectively identified genes associated with hypertension disease than MetaSKAT did.

241-LB: Identification of Novel and Population-Specific Signals for Type 2 Diabetes in Large-Scale Study of Hispanic/Latino Individuals

Hispanic/Latino populations are both disproportionately burdened by type 2 diabetes (T2D) and drastically less studied compared to non-Hispanic whites. We present results of the final data freeze of the DIAMANTE Hispanic/Latino Consortium, comprising the largest genome-wide meta-analysis and transcriptome-wide association study of T2D in a Hispanic/Latino population and including a total of 13,151 T2D cases and 21,511 controls. We identified a novel locus in an intronic region of BACE1 for T2D adjusted for body mass index, which has previously been linked to gestational diabetes susceptibility, but never before to T2D. We also identified two variants in known loci with evidence (p &amp;lt;1x10-5) of a residual effect after adjusting for the closest known variant, suggesting that these may be population-specific effects due to H/L linkage disequilibrium structure. We used S-PrediXcan to compute the association of tissue-specific imputed expression for 48 tissues with T2D, revealing novel associations with ten genes and replicating six known genes. These novel genes include three genes previously associated with blood pressure traits: MOV10, ST7L, and WNT2B, as well as two genes previously associated with adiposity, measured by waist and hip circumference: MOV10 and WNT2B. Three novel genes have compelling evidence due to known roles of their biological pathways, including PTCH1, in the hedgehog pathway, which is known to play a role in pancreas development, ST7L, which is a miR-24 target and previous studies have indicated that miR-24 is elevated in diabetes, and WNT2B, part of the WNT signaling pathway, which is known to be involved in glucose homeostasis. These results demonstrate that genetic study of T2D in H/L populations can both help prevent a major health disparity through inclusion of this henceforth overlooked population and can also enable further discovery. Disclosure L.E. Petty: None. J.E. Below: None.

A multi-ancestry genome-wide study incorporating gene-smoking interactions identifies multiple new loci for pulse pressure and mean arterial pressure.

Elevated blood pressure (BP), a leading cause of global morbidity and mortality, is influenced by both genetic and lifestyle factors. Cigarette smoking is one such lifestyle factor. Across five ancestries, we performed a genome-wide gene-smoking interaction study of mean arterial pressure (MAP) and pulse pressure (PP) in 129 913 individuals in stage 1 and follow-up analysis in 480 178 additional individuals in stage 2. We report here 136 loci significantly associated with MAP and/or PP. Of these, 61 were previously published through main-effect analysis of BP traits, 37 were recently reported by us for systolic BP and/or diastolic BP through gene-smoking interaction analysis and 38 were newly identified (P < 5 × 10-8, false discovery rate < 0.05). We also identified nine new signals near known loci. Of the 136 loci, 8 showed significant interaction with smoking status. They include CSMD1 previously reported for insulin resistance and BP in the spontaneously hypertensive rats. Many of the 38 new loci show biologic plausibility for a role in BP regulation. SLC26A7 encodes a chloride/bicarbonate exchanger expressed in the renal outer medullary collecting duct. AVPR1A is widely expressed, including in vascular smooth muscle cells, kidney, myocardium and brain. FHAD1 is a long non-coding RNA overexpressed in heart failure. TMEM51 was associated with contractile function in cardiomyocytes. CASP9 plays a central role in cardiomyocyte apoptosis. Identified only in African ancestry were 30 novel loci. Our findings highlight the value of multi-ancestry investigations, particularly in studies of interaction with lifestyle factors, where genomic and lifestyle differences may contribute to novel findings.

Generality of genomic findings on blood pressure traits and its usefulness in precision medicine in diverse populations: A systematic review.

Remarkable findings from genome-wide association studies (GWAS) on blood pressure (BP) traits have made new insights for developing precision medicine toward more effective screening measures. However, generality of GWAS findings in diverse populations is hampered by some technical limitations. There is no comprehensive study to evaluate source(s) of the non-generality of GWAS results on BP traits, so to fill the gap, this systematic review study was carried out. Using MeSH terms, 1545 records were detected through searching in five databases and 49 relevant full-text articles were included in our review. Overall, 749 unique variants were reported, of those, majority of variants have been detected in Europeans and were associated to systolic and diastolic BP traits. Frequency of genetic variants with same position was low in European and non-European populations (n = 38). However, more than 200 (>25%) single nucleotide polymorphisms were found on same loci or linkage disequilibrium blocks (r2 ≥ 80%). Investigating for locus position and linkage disequilibrium of infrequent unique variants showed modest to high reproducibility of findings in Europeans that in some extent was generalizable in other populations. Beyond theoretical limitations, our study addressed other possible sources of non-generality of GWAS findings for BP traits in the same and different origins.

The Impact of APOL1 on Chronic Kidney Disease and Hypertension.

Essential hypertension is a clinical diagnosis based on the presence of an elevated systemic blood pressure on physical examination without a clear inciting cause. It has multiple etiologies and is not a homogeneous disorder. Hypertension contributes to the development and progression of atherosclerotic cardiovascular diseases, and antihypertensive treatment reduces the risk of fatal and nonfatal myocardial infarction, stroke, and congestive heart failure. Although hypertension is frequently present in nondiabetic individuals with low levels of proteinuria and chronic kidney disease, reducing blood pressures in this population does not reliably slow nephropathy progression. Many of these patients with recent African ancestry have the primary kidney disease "solidified glomerulosclerosis" that is strongly associated with renal-risk variants in the apolipoprotein L1 gene (APOL1). This kidney disease contributes to secondarily elevated blood pressures. The APOL1-associated spectrum of nondiabetic nephropathy also includes proteinuric kidney diseases, idiopathic focal segmental glomerulosclerosis, collapsing glomerulopathy, severe lupus nephritis, and sickle cell nephropathy. This article reviews relationships between mild to moderate essential hypertension and chronic kidney disease with a focus on the role of APOL1 in development of hypertension. Available evidence strongly supports that APOL1 renal-risk variants associate with glomerulosclerosis in African Americans, which then causes secondary hypertension, not with essential hypertension per se.

Gene-environment interactions related to blood pressure traits in two community-based Korean cohorts.

Hypertension is a complex disorder caused by genetic and environmental risk factors. Recently, genome-wide association studies (GWASs) identified more than 100 genetic variants for blood pressure traits and hypertension. However, the interactions between these genetic variants and environmental factors have not been systematically investigated. Therefore, we examined the interaction between genetic and environmental risk factors in blood pressure traits using the genetic risk score (GRS). Two Korean community-based cohorts, Cohort I (KARE; N = 8,840) and Cohort II (CAVAS; N = 9,599), were used for this study, and GRSs were calculated from 42 GWAS single-nucleotide polymorphisms (SNPs) that were validated for their association in these cohorts. We calculated GRSs in both ways by considering the effect sizes of each SNP (weighted GRS) and not considering the effect sizes (unweighted GRS). The unweighted GRS was strongly associated with systolic blood pressure, diastolic blood pressure, and hypertension (p = 9.03 × 10 -47 , p = 9.41 × 10 -48 , and p = 3.22 × 10 -55 by meta-analysis, respectively) and the weighted GRS showed the similar results. The environmental factors of body mass index, waist circumference, and drinking status were significantly associated with blood pressure traits, and the interaction between these factors and GRSs were examined. However, no interactions were found witheither the GRS or the individual SNPs considered for the GRS. Our findings show that it is challenging to find GRS-environment interactions regarding blood pressure traits.

Leveraging linkage evidence to identify low-frequency and rare variants on 16p13 associated with blood pressure using TOPMed whole genome sequencing data.

In this study, we investigated low-frequency and rare variants associated with blood pressure (BP) by focusing on a linkage region on chromosome 16p13. We used whole genome sequencing (WGS) data obtained through the NHLBI Trans-Omics for Precision Medicine (TOPMed) program on 395 Cleveland Family Study (CFS) European Americans (CFS-EA). By analyzing functional coding variants and non-coding rare variants with CADD score > 10 residing within the chromosomal region in families with linkage evidence, we observed 25 genes with nominal statistical evidence (burden or SKAT p < 0.05). One of the genes is RBFOX1, an evolutionarily conserved RNA-binding protein that regulates tissue-specific alternative splicing that we previously reported to be associated with BP using exome array data in CFS. After follow-up analysis of the 25 genes in ten independent TOPMed studies with individuals of European, African, and East Asian ancestry, and Hispanics (N = 29,988), we identified variants in SLX4 (p = 2.19 × 10-4) to be significantly associated with BP traits when accounting for multiple testing. We also replicated the associations previously reported for RBFOX1 (p = 0.007). Follow-up analysis with GTEx eQTL data shows SLX4 variants are associated with gene expression in coronary artery, multiple brain tissues, and right atrial appendage of the heart. Our study demonstrates that linkage analysis of family data can provide an efficient approach for detecting rare variants associated with complex traits in WGS data.

Genetic and lifestyle risk factors for MRI-defined brain infarcts in a population-based setting.

ObjectiveTo explore genetic and lifestyle risk factors of MRI-defined brain infarcts (BI) in large population-based cohorts.MethodsWe performed meta-analyses of genome-wide association studies (GWAS) and examined associations of vascular risk factors and their genetic risk scores (GRS) with MRI-defined BI and a subset of BI, namely, small subcortical BI (SSBI), in 18 population-based cohorts (n = 20,949) from 5 ethnicities (3,726 with BI, 2,021 with SSBI). Top loci were followed up in 7 population-based cohorts (n = 6,862; 1,483 with BI, 630 with SBBI), and we tested associations with related phenotypes including ischemic stroke and pathologically defined BI.ResultsThe mean prevalence was 17.7% for BI and 10.5% for SSBI, steeply rising after age 65. Two loci showed genome-wide significant association with BI: FBN2, p = 1.77 × 10−8; and LINC00539/ZDHHC20, p = 5.82 × 10−9. Both have been associated with blood pressure (BP)–related phenotypes, but did not replicate in the smaller follow-up sample or show associations with related phenotypes. Age- and sex-adjusted associations with BI and SSBI were observed for BP traits (p value for BI, p[BI] = 9.38 × 10−25; p[SSBI] = 5.23 × 10−14 for hypertension), smoking (p[BI] = 4.4 × 10−10; p[SSBI] = 1.2 × 10−4), diabetes (p[BI] = 1.7 × 10−8; p[SSBI] = 2.8 × 10−3), previous cardiovascular disease (p[BI] = 1.0 × 10−18; p[SSBI] = 2.3 × 10−7), stroke (p[BI] = 3.9 × 10−69; p[SSBI] = 3.2 × 10−24), and MRI-defined white matter hyperintensity burden (p[BI] = 1.43 × 10−157; p[SSBI] = 3.16 × 10−106), but not with body mass index or cholesterol. GRS of BP traits were associated with BI and SSBI (p ≤ 0.0022), without indication of directional pleiotropy.ConclusionIn this multiethnic GWAS meta-analysis, including over 20,000 population-based participants, we identified genetic risk loci for BI requiring validation once additional large datasets become available. High BP, including genetically determined, was the most significant modifiable, causal risk factor for BI.

Genetic determinants of blood pressure traits are associated with carotid arterial thickening and plaque formation in patients with type 2 diabetes

The aim of this study is to explore the contribution of genetically driven cardiometabolic risk factors for development of carotid arterial thickening in patients with type 2 diabetes. In total, 12 genetic risk scores for blood pressure, blood lipids and glycaemic traits were constructed. The genetic risk scores were tested for association with carotid intima-media thickness and plaques in patients with type 2 diabetes ( n = 401) and in non-diabetic individuals ( n = 648) and for association with glucose levels in two population-based cohorts ( n = 1328 and n = 6161). In patients with type 2 diabetes, the genetic risk scores for pulse pressure were positively associated with plaque formation ( β = 0.036 ± 0.01 standard deviation/allele, p = 0.003). The genetic risk score for diastolic blood pressure was negatively associated with carotid intima-media thickness ( β = -0.037 ± 0.01 standard deviation/allele, p = 0.005), although not significant after correction for multiple testing ( p < 0.0042). In a meta-analysis of individuals with and without type 2 diabetes, the high-density lipoprotein genetic risk scores showed a trend towards an inverse association with carotid intima-media thickness and plaques, while the low-density lipoprotein genetic risk scores showed a trend towards a positive association with plaque formation but did reach the statistical threshold. Genetic loci for pulse pressure are associated with plaque formation among patients with type 2 diabetes, suggesting an underlying genetic contribution to arterial stiffening and atherosclerosis.

Interactions of CDH13 gene polymorphisms and ambient PM10 air pollution exposure with blood pressure and hypertension in Korean men

Associations between air pollution and blood pressure (BP) traits can be modified by several candidate genes, which might explain differences in individual genetic susceptibility. Based on recent evidence hypothesized to link air pollution and BP traits, we examined whether the polymorphisms of CDH13—a candidate gene—would modify the relationship between them in adult Korean men. A total of 1816 subjects were included. We divided them into two groups of high or low to moderate exposure using the annual average concentration of particulate matter with an aerodynamic diameter ≤10 μm (PM10). We conducted an interaction analysis of PM10 exposure using 200 single-nucleotide polymorphisms (SNPs), located within CDH13, in subjects with regard to BP traits and hypertension. The rs7500599 intronic SNP of CDH13 had the strongest signals for all BP traits including systolic blood pressure (SBP), diastolic blood pressure, and hypertension, by interacting with PM10 exposure. An additional stratified analysis showed that the effects of PM10 exposure on elevated BP and hypertension increased gradually in proportion to the number of minor alleles in this SNP. In addition, PM10 exposure in the TT or GT genotype groups did not show significant associations with BP traits, whereas in a homozygous risk allele (GG) group, PM10 exposure was significantly associated with BP traits and hypertension. For SBP, these patterns were reproducible at two independent sampling sites. This CDH13 polymorphism amplifies the negative associations of PM10 exposure and elevated BP or hypertension in Korean men.

Publisher Correction: Genetic analysis of over 1 million people identifies 535 new loci associated with blood pressure traits.

In the version of this article originally published, the name of author Martin H. de Borst was coded incorrectly in the XML. The error has now been corrected in the HTML version of the paper.

Generalizing polygenic risk scores from Europeans to Hispanics/Latinos.

Polygenic risk scores (PRSs) are weighted sums of risk allele counts of single-nucleotide polymorphisms (SNPs) associated with a disease or trait. PRSs are typically constructed based on published results from Genome-Wide Association Studies (GWASs), and the majority of which has been performed in large populations of European ancestry (EA) individuals. Althoughmany genotype-trait associations have generalized across populations, the optimal choice of SNPs and weights for PRSs may differ between populations due to different linkage disequilibrium (LD) and allele frequency patterns. We compare various approaches for PRS construction, using GWAS results from both large EA studies and a smaller study in Hispanics/Latinos: The Hispanic Community Health Study/Study of Latinos (HCHS/SOL, ). We consider multiple approaches for selecting SNPs and for computing SNP weights. We study the performance of the resulting PRSs in an independent study of Hispanics/Latinos from the Women's Health Initiative (WHI, ). We support our investigation with simulation studies of potential genetic architectures in a single locus. We observed that selecting variants based on EA GWASs generally performs well, except for blood pressure trait. However, the use of EA GWASs for weight estimation was suboptimal. Using non-EA GWAS results to estimate weights improved results.

Plasma Steroids are Not Associated with Resting and Exercise Blood Pressure.

We investigated the associations between steroid hormones and resting and exercise blood pressure in the sedentary state and in response to an exercise program controlling for sex, body mass, ethnicity, age, oral contraceptives, hormone therapy, smoking and alcohol intake in subjects from the HERITAGE Family Study.: In the sedentary state, 267 men (28% Blacks) and 301 women (37% Blacks) were available, and 241 men and 254 women completed the exercise program. Fourteen steroid hormones and sex hormone-binding globulin concentrations were assayed in a fasted state. Statistical significance was set at a Bonferroni adjusted p<0.0001. After controlling for the various covariates, only testosterone came close to a significant correlation with exercise systolic blood pressure at 50 W (r=-0.21, P=0.0006) in men. No other correlations with resting and exercise blood pressure traits were found at baseline. There were significant changes in blood pressure in response to the exercise program, but none of the correlations with baseline plasma steroids reached statistical significance. Plasma steroids do not correlate with resting and exercise blood pressure in sedentary adults and do not associate with blood pressure changes in response to a 20-week endurance exercise program.

Combined linkage and association analysis identifies rare and low frequency variants for blood pressure at 1q31.

High blood pressure (BP) is a major risk factor for cardiovascular disease (CVD) and is more prevalent in African Americans as compared to other US groups. Although large, population-based genome-wide association studies (GWAS) have identified over 300 common polymorphisms modulating inter-individual BP variation, largely in European ancestry subjects, most of them do not localize to regions previously identified through family-based linkage studies. This discrepancy has remained unexplained despite the statistical power differences between current GWAS and prior linkage studies. To address this issue, we performed genome-wide linkage analysis of BP traits in African-American families from the Family Blood Pressure Program (FBPP) and genotyped on the Illumina Human Exome BeadChip v1.1. We identified a genomic region on chromosome 1q31 with LOD score 3.8 for pulse pressure (PP), a region we previously implicated in DBP studies of European ancestry families. Although no reported GWAS variants map to this region, combined linkage and association analysis of PP identified 81 rare and low frequency exonic variants accounting for the linkage evidence. Replication analysis in eight independent African ancestry cohorts (N = 16,968) supports this specific association with PP (P = 0.0509). Additional association and network analyses identified multiple potential candidate genes in this region expressed in multiple tissues and with a strong biological support for a role in BP. In conclusion, multiple genes and rare variants on 1q31 contribute to PP variation. Beyond producing new insights into PP, we demonstrate how family-based linkage and association studies can implicate specific rare and low frequency variants for complex traits.

Genetic analysis of over 1 million people identifies 535 new loci associated with blood pressure traits.

High blood pressure is a highly heritable and modifiable risk factor for cardiovascular disease. We report the largest genetic association study of blood pressure traits (systolic, diastolic and pulse pressure) to date in over 1 million people of European ancestry. We identify 535 novel blood pressure loci that not only offer new biological insights into blood pressure regulation but also highlight shared genetic architecture between blood pressure and lifestyle exposures. Our findings identify new biological pathways for blood pressure regulation with potential for improved cardiovascular disease prevention in the future.

Stress, Genes, and Hypertension. Contribution of the ISIAH Rat Strain Study.

Acute psychoemotional stress is one of the causes of a sharp increase in blood pressure. However, the question if the stress may promote the hypertensive disease development is still open. This review aims, firstly, to show that the genetically determined enhanced responsiveness to stress is linked to sustained hypertension development and, secondly, to characterize the main physiological mechanisms and genetic factors implicated in the pathogenesis of stress-sensitive hypertension. Recent findings helped to characterize the main neuroendocrine mechanisms and the specificity of the genetic background contributing to the stress-sensitive hypertension development in the ISIAH rats. The ISIAH rat strain, which is an original model of the stress-sensitive arterial hypertension, can be considered as "living" proof that the genetic predisposition to increased stress-reactivity can lead to the development of persistent stress-dependent arterial hypertension. The ISIAH rat strain is characterized by the genetically determined enhanced response of the neuroendocrine and renal regulatory systems to stress and is a suitable model that allows one to explore the genetic and physiological mechanisms involved in stress-sensitive hypertension development. There are common genetic loci (QTLs) associated with both basal and stress-induced blood pressure (BP) levels as well as QTLs associated with BP and other traits, which may be related to hypertension development in ISIAH rats. Multiple genes differentially expressed in the target organs/tissues of hypertensive ISIAH and normotensive control rats are associated with many biological processes and metabolic pathways involved in stress response and arterial hypertension. The genotype of ISIAH rats is characterized by numerous specific and common SNPs as compared with other models of hypertensive rats. The results of the studies are valuable for the search for genetic markers specific for stress-induced arterial hypertension, as well as for the selection of new molecular targets that may be potentially useful for prevention and/or therapy of hypertensive disease.

Genetic and Environmental Contributions to the Covariation Between Cardiometabolic Traits.

BackgroundThe variation and covariation for many cardiometabolic traits have been decomposed into genetic and environmental fractions, by using twin or single‐nucleotide polymorphism (SNP) models. However, differences in population, age, sex, and other factors hamper the comparison between twin‐ and SNP‐based estimates.Methods and ResultsTwenty‐four cardiometabolic traits and 700,000 genotyped SNPs were available in the study base of 10 682 twins from TwinGene cohort. For the 27 highly correlated pairs (absolute phenotypic correlation coefficient ≥0.40), twin‐based bivariate structural equation models were performed in 3870 complete twin pairs, and SNP‐based bivariate genomic relatedness matrix restricted maximum likelihood methods were performed in 5779 unrelated individuals. In twin models, the model including additive genetic variance and unique/nonshared environmental variance was the best‐fitted model for 7 pairs (5 of them were between blood pressure traits); the model including additive genetic variance, common/shared environmental variance, and unique/nonshared environmental variance components was best fitted for 4 pairs, but estimates of shared environment were close to zero; and the model including additive genetic variance, dominant genetic variance, and unique/nonshared environmental variance was best fitted for 16 pairs, in which significant dominant genetic effects were identified for 13 pairs (including all 9 obesity‐related pairs). However, SNP models did not identify significant estimates of dominant genetic effects for any pairs. In the paired t test, twin‐ and SNP‐based estimates of additive genetic correlation were not significantly different (both were 0.67 on average), whereas the nonshared environmental correlations from these 2 models differed slightly from each other (on average, twin‐based estimate=0.64 and SNP‐based estimate=0.68).ConclusionsBeside additive genetic effects and nonshared environment, nonadditive genetic effects (dominance) also contribute to the covariation between certain cardiometabolic traits (especially for obesity‐related pairs); contributions from the shared environment seem to be weak for their covariation in TwinGene samples.