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We aimed at associating common osteopontin (OPN) gene variants with cardiovascular disease phenotypes.We scanned the OPN gene in 190 chromosomes from myocardial infarction (MI) patients and identified five variants in the promoter, three synonymous and one non-synonymous variant. All variants were investigated in case–control studies for MI (ECTIM: 990 cases, 900 controls) and brain infarction (BI) (GENIC: 466 cases, 444 controls). Promoter variants were functionally analyzed by bandshift assays, the coding D147D [T/C] by Western blot. Allele D147D C was independently and significantly associated with lower apoB levels ( P =0.044 [ECTIM] P =0.03 [GENIC]), its allele frequency was significantly lower in patients with BI compared to controls (OR [95% CI] 0.39 [0.20–0.74], P =0.004), and C allele carriers had a significantly lower frequency of presence of carotid plaques ( P =0.02). Bandshifts with HepG2 and Ea.hy926 nuclear proteins did not reveal any functionality of promoter variants, whereas the OPN-441C-containing construct resulted in reduced OPN protein expression in Western blots, complying with its potential protective effect on the phenotypes studied.We here provide evidence that a portion of the OPN locus is likely to associate with cardiovascular disease-related phenotypes. However, further experiments are warranted to clarify the functional role of OPN variants.

See related articles, pages 1109–1120. Cardiovascular disease (CVD), including coronary artery disease (CAD) with its fatal clinical outcome myocardial infarction (MI) and stroke, remain the leading cause of deaths in western and nonwestern countries.1,2 In the US, CVD claims more lives than cancer, chronic lower respiratory tract diseases and diabetes mellitus combined, accounting for ≈36% of all deaths in 2004 and incurring an estimated direct and indirect cost of ≈432 billion dollars in 2007.2 Stroke and MI are multifactorial traits with complex pathophysiology. Besides other established factors, family history of disease strongly and independently determines CVD risk.3 There is a nearly 5-fold difference in stroke risk between monocygotic and dizygotic twins,4 and with respect to race, stroke incidence is approximately twice as high in blacks compared to whites.5 Marenberg et al,6 in their study on ≈20 000 Swedish twins, demonstrated that the relative risk to die from MI, when the other twin already died from this disease, was twice as large for monozygotic compared to dizygotic twins. Celera Genomics7 and the International Human Genome Project consortium,8 by whole genome shotgun and clone-based sequencing strategies, respectively, proposed 2 versions of the human genome—the diploid genome offering more genetic information than previously anticipated.9 The availability of almost the entire human genome sequence allows for the immediate access to specific target sequences across the human genome. The number of different technologies to explore genetic sequences on a “genome-wide” scale and high-throughput genotyping methods is steadily increasing. Genome-wide approaches are essentially based on the fact that alleles at nearby loci often show strong linkage disequilibrium (LD). Human recombination events occur ubiquitously in short genomic hotspots (1 to 2 kb) every 100 to 200 kb, preferentially outside genes,10 leading to a breakdown of allelic …

Objective The SAH gene locus has recently been proposed to be involved in obesity-related hypertension in Japanese individuals. Methods To replicate independently the initial findings in another ethnic group, we scanned the entire SAH gene in 190 Caucasian chromosomes. A total of 651 patients with essential hypertension and 776 controls (PEGASE Study) were genotyped for all identified variants using allele-specific oligonucleotides, and single nucleotide polymorphism as well as haplotype analyses were carried out. We also performed transient transfection experiments, northern and western blots, immunoprecipitation, and acyl-coenzyme A synthetase activity assays. Results We identified five polymorphisms in the promoter region (C−1808T, G−1606A, −962ins/del, G−451A, T−67C), two in introns 5 and 7 (T+9/In5C, A+20/In7T), and one missense variant (K359N). Carriage of the −1606A allele was significantly associated with hypertension [odds ratio (OR) 1.28, P = 0.049] as was 359N (OR 1.35, P = 0.048) compared with non-carriers. Conversely, for −962del, the OR for hypertension was 0.80 (P = 0.042). The SAH alleles −1606A and 359N, but not −962ins/del, displayed a raising effect on body mass index (BMI; P = 0.004 and P = 0.030, respectively) in hypertensive as well as in control individuals. After adjustment for BMI in hypertensive individuals, only the OR associated with −962ins/del remained significant (OR 0.77, P = 0.028). Functional analyses in BHK did not reveal differences for SAH 359N or 359K-containing constructs, formally excluding K359N as the functional variant. Conclusion We confirm recent evidence that the SAH locus is associated with obesity-related hypertension, in which pathophysiological context SAH variants affecting blood pressure remain, however, to be shown.

Hypertension is a chronic age-related disorder, affecting nearly 20% of all adult Europeans. This disease entails debilitating cardiovascular complications and is the leading cause for drug prescriptions in Europeans older then 50 years. Intensive research over the past two decades failed so far to identify common genetic polymorphisms with major impact on blood pressure or associated cardiovascular phenotypes, suggesting that multiple genes each with a minor impact, along with gene-gene and gene-environment interactions play a role. The European Project on Genes in Hypertension (EPOGH) is a large-scale family-based study, in which participants from 7 different populations were phenotyped and genotyped according to standardised procedures. This review article summarizes the initial 5-year findings and puts these observations into perspective against other published studies. EPOGH demonstrated that phenotype-genotype relations strongly depend on host factors, such as gender and lifestyle, in particular salt intake as reflected by the 24-hour urinary excretion of sodium. EPOGH therefore highlights the concept that phenotype-genotype relations can only be studied within a defined ecogenetic context. © 2006 Bentham Science Publishers Ltd. ispartof: Current Hypertension Reviews vol:2 issue:4 pages:275-281 status: published

Background and Purpose— Carotid intima-media thickness (IMT) reflects generalized atherosclerosis and is predictive of future vascular events. Evidence exists that carotid IMT is heritable, and genetic studies can provide clues in the pathogenesis of atherosclerosis. Methods— We recruited 470 white ischemic stroke patients, measured common carotid artery (CCA) IMT, and analyzed 54 polymorphisms with suspected roles in atherosclerosis. Results— Among the polymorphisms tested, the angiotensin-converting enzyme insertion/deletion, osteopontin (OPN) T-443C, monocyte chemoattractant protein-1 (MCP-1) G-927C, and MCP-1 A-2578G polymorphisms were associated with CCA–IMT in age-gender–adjusted analysis. In multivariate analysis, the association between the OPN and MCP-1 polymorphisms remained significant. The OPN-443C allele was associated with increased IMT in the dominant model (0.053 mm for the TC and CC genotypes; P =0.001). The MCP-1-927C allele was associated with increased IMT in the additive model (0.040 mm for each C allele; P =0.001), and the MCP-1-2578 G allele was associated with decreased IMT in the recessive model (0.088 mm for the GG genotype; P =0.002). Conclusions— The OPN and MCP-1 genes, coding for 2 cytokines with known roles in atherosclerosis, may contribute to increased carotid IMT and warrant further study.

Earlier studies have demonstrated the interaction between ADD1 and ACE in relation to arterial properties. We investigated whether arterial characteristics might also be related to interactions of ADD1 with other renin-angiotensin system genes. Using a family-based sampling frame, we randomly recruited 1064 Flemish subjects (mean age, 43.6 years; 50.4% women). By means of a wall-tracking ultrasound system, we measured the properties of the carotid, femoral and brachial arteries. In multivariate-adjusted analyses, we assessed the multiple gene effects of ADD1 (Gly460Trp), AGT (C-532T and G-6A) and AT1R (A1166C). In ADD1 Trp allele carriers, but not in ADD1 GlyGly homozygotes (P-value for interaction < or =0.014), femoral cross-sectional compliance was significantly higher (0.74 vs 0.65 mm(2) kPa(-1); P=0.020) in carriers of the AT1R C allele than in AT1R AA homozygotes, with a similar trend for femoral distensibility (11.3 vs 10.2 x 10(-3) kPa(-1); P=0.055). These associations were independent of potential confounding factors, including age. Family-based analyses confirmed these results. Brachial diameter (4.35 vs 4.18 mm) and plasma renin activity (PRA) (0.23 vs 0.14 ng ml(-1) h(-1)) were increased (P< or =0.005) in AGT CG haplotype homozygotes compared with non-carriers, whereas the opposite was true for brachial distensibility (12.4 vs 14.4 x 10(-3) kPa(-1); P=0.011). There was no interaction between AGT and any other gene in relation to the measured phenotypes. ADD1 and AT1R interactively determine the elastic properties of the femoral artery. There is a single-gene effect of the AGT promoter haplotypes on brachial properties and PRA. ispartof: Journal of Human Hypertension vol:23 issue:1 pages:55-64 ispartof: location:England status: published

A priority in preventive cardiology is to reduce the number of recurrent events and to prolong survival in patients with established coronary heart disease (CHD). Aim of the present study was to examine risk factors for long-term mortality in CHD patients who entered routine secondary prevention after a coronary event or intervention. Such patients, from the EUROASPIRE (EUROpean Action on Secondary Prevention through Intervention to Reduce Events) I and II studies in the region of Munster, Germany, were followed over a mean period of 8.0 years up to the end of 2005. Patients were up to 70 years of age at baseline when they were interviewed and examined using standardised methods. Baseline examination was carried out at least 6 months and at a mean of 19.5 months after the coronary event or procedure. In 367 patients from EUROASPIRE I and 380 patients from EUROASPIRE II, a total of 125 deaths (16.7%) occurred during follow-up. Multivariate analyses, using Cox proportional hazards models, established diabetes mellitus and smoking as predictors for all-cause mortality with estimated hazard rate ratios (HRRs) of 2.24 (95% confidence interval (CI): 1.43-3.49) and 1.95 (95% CI: 1.23-3.10), respectively. Significant associations were found between diabetes mellitus and cardiovascular (HRR 2.36; 95% CI: 1.31-4.24) as well as CHD mortality (HRR 2.40; 95% CI: 1.25-4.59). Systolic blood pressure was significantly associated with increased cerebrovascular disease mortality (HRR 1.04; 95% CI: 1.01 and 1.08 for 1 mmHg increase). In conclusion, long-term mortality in coronary patients from routine secondary prevention is substantial. Diabetes mellitus and smoking represent key issues in patients with established CHD.

Background The endothelin system (ES) plays an important role in blood pressure (BP) regulation and also in the pathophysiology of idiopathic dilated cardiomyopathy (DCM). Recently, we demonstrated that a genetic polymorphism in the endothelin A (ET A ) receptor gene was associated with survival in DCM patients. The aim of this study was to determine whether polymorphisms in the ET A receptor gene might be associated with the severity of DCM. Methods One hundred twenty-four consecutively recruited unrelated patients with DCM, who underwent a detailed phenotyping protocol, were genotyped for the ET A receptor G-231A polymorphism using a hybridization technique with allele-specific oligonucleotides. Results The exon 1 G-231A polymorphism of the ET A receptor gene, upstream of the translation start site, was significantly associated with directly measured intra-aortic pressure in that −231A allele carriers had significantly lower systolic ( P = .0043), as well as mean ( P = .0016) and diastolic ( P = .0041) aortic pressure compared to noncarriers. The association of ET A G-231A with aortic pressure was independent from other factors such as prior medication, left ventricular end-diastolic diameter, age, gender, and New York Heart Association (NYHA) functional classification. However, no such association was seen for cuff BP and survival rates were not significantly different between −231A allele carriers and −231G homozygotes (log rank test, P = .66). No significant association with any other parameter investigated in the present study could be observed, even when men and women were analyzed separately. Conclusions Our results suggest an association of genetic variation in the ET A receptor gene with aortic pressure in patients with DCM.

Hypertension is a chronic age-related disorder, affecting nearly 20% of all adult Europeans. This disease entails debilitating cardiovascular complications and is the leading cause for drug prescriptions in Europeans older than 50 years. Intensive research over the past two decades has so far failed to identify common genetic polymorphisms with a major impact on blood pressure or associated cardiovascular phenotypes, suggesting that multiple genes each with a minor impact, along with gene-gene and gene-environment interactions, play a role. The European Project on Genes in Hypertension (EPOGH) is a large-scale, family-based study in which participants from seven different populations were phenotyped and genotyped according to standardized procedures. This review article summarizes the initial 5-year findings and puts these observations into perspective against other published studies. The EPOGH demonstrated that phenotype-genotype relations strongly depend on host factors such as gender and lifestyle, in particular salt intake as reflected by the 24-h urinary excretion of sodium. The EPOGH therefore highlights the concept that phenotype-genotype relations can only be studied within a defined ecogenetic context. ispartof: Journal of hypertension vol:24 issue:2 pages:235-42 ispartof: location:Netherlands status: published