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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.

Aims Identification and functional characterization of variants in the neutrophil elastase (ELA2) gene in cardiovascular disease. Methods From participants of the ECTIM (Etude Cas-Temoins sur l'infarctus du Myocarde) Study with myocardial infarction (Ml) 2082 chromosomes were genetically scanned; 990 patients with Ml and 904 controls were genotyped for the common polymorphisms G-761A and S173S (C4890A). Expression vectors for Ela2 variants were transiently transfected, followed by Northern and Western blot analyses. Promoter variants were analyzed by transfection/reporter gene assays. Results We identified 11 genetic variants, two in the 5'-flanking (G-761A, -852/del53bp), six in exons (R49H, N81N, G93V, S173S, D222Y, P228L) and three in introns (C+29/in3T, C+149/in3T, C+137/in4T). In Belfast, 4890A allele carriers had a risk for Ml with an odds ratio (OR) of 1.44 (95% Cl 1.12-1.86; P= 0.005), the OR for Ml associated with the - 761 G/-4890A haplotype with reference to -761G/-4890C amounting to 2.38 (95% Cl 1.23-4.57; P=0.01). Transcript or protein expression of both allelic constructs (4890A and 4890C) did not, however, differ. Conversely, transcriptional activity was significantly elevated (

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.

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.

Background The polymorphic angiotensinogen (AGT) gene is one of the most promising candidates for blood pressure (BP) regulation and essential hypertension. Objectives To investigate whether AGT haplotype analysis adds significant information compared to single polymorphism analysis with respect to different BP phenotypes in an untreated hypertensive sample. Methods Two hundred and twelve untreated hypertensive subjects of Caucasian origin were genotyped for the AGT polymorphisms C-532T, A-20C, C-18T, and G-6A. Results In single variant analyses, untreated hypertensives, carrying the AGT -532T or -6A alleles had significantly higher systolic blood pressure (SBP) and diastolic blood pressure (DBP), as well as ambulatory BP values compared to respective non-carriers. In haplotype-based analyses, combining all four AGT promoter variants, we demonstrate that AGT haplotypes containing different allele combinations at positions -532 and -6 were significantly associated with different BP values: (1) -532T and -6A with higher, (2) -532C and -6G with lower, (3) -532C and -6A with intermediate BP values. Since the result for the -532C/-20A/-18C/-6G haplotype was due to differences between non-carriers and carriers of this haplotype on both chromosomes, a recessive inheritance model for BP effects could be assumed. Conclusions Our results designate the C-532T and G-6A as the best candidates for functional studies on the AGT gene. Haplotype-based analyses should greatly aid in the dissection of the genetic basis of complex traits, such as BP regulation and hypertension.

Gardner syndrome, a phenotypic variant of familial adenomatous polyposis, is characterized by the classical clinical triad of skin and soft tissue tumours, osteomas and intestinal polyposis, but disease patterns with pairs of these findings have also been reported. Different mutations in the adenomatous polyposis coli (APC) gene have been shown to be associated with Gardner syndrome disease phenotypes. A 36-year-old patient presented with multiple epidermal cysts on the face, left ear lobe and neck, and the possible diagnosis of Gardner syndrome was based on the additional findings of two classical osteomas in the left radius and ulna and a cold non-malignant nodule of the thyroid gland. Intestinal polyposis was lacking at the time of examination. Major deletions but not microdeletions were excluded by a cytogenetic analysis with 650 chromosomal bands per haploid set. Systematic sequencing of the entire coding region of the APC gene (> 8500 bp) of the patient and five healthy controls was also performed. As a results, new APC gene polymorphisms were identified in exons 13 [A545A (A/G)] and 15 [G1678G (A/G), S1756S (G/T), P1960P (A/G)]. We also detected D1822V (A/T) which has recently been reported to be potentially related to colorectal carcinoma, and genotyped 194 randomly chosen healthy individuals from the Glasgow area for this as well as for the above variants in exons 13 and 15. Interestingly, of the 194 controls, 112 carried the DD (57.7%), 71 the DV (36.6%), and the remaining 11 (5.7%), including our patient, the VV genotype. It is therefore unlikely that APC D1822V serves as an important marker for colorectal carcinoma. In conclusion, we failed to identify obvious germline candidate mutations in > 8500 bp of the coding region of the APC gene in a patient with multiple epidermal cysts, osteomas and a thyroid gland nodule; major chromosomal deletions were excluded. Therefore, we assume that only the presence of intestinal polyposis is a marker for Gardner syndrome.

A decreased GFR in the range of mild renal insufficiency and an increased urinary albumin excretion (UAE) rate in the range of microalbuminuria are important cardiovascular risk factors. Endothelin-1 (ET-1) has been suggested to be a major disease promoting factor in renal disease. The role of the ET-1 gene locus (EDN1) for renal function in the general nondiabetic population was evaluated. To explore the overall relevance of EDN1, two suitable single-nucleotide polymorphisms, EDN1 K198N and EDN1 T-1370G, were selected, and haplotype analysis was performed. Determined were genotypes in 7291 nondiabetic subjects from the Prevention of Renal and Vascular End-Stage Disease (PREVEND) study. Genetic analysis was related to UAE and GFR as continuous variables and to microalbuminuria and diminished filtration as dichotomous traits. In a logistic regression analysis, no significant higher risk for increased UAE, microalbuminuria, decreased GFR, or diminished filtration could be observed for either single-nucleotide polymorphism separately. Haplotype analysis revealed that individuals with the homozygous G-N haplotype (compound EDN1 - 1370GG/198NN genotype) have a lower GFR than the remaining subjects (P

The angiotensin II type 2 (AT2) receptor is thought to play a role in cardiovascular disorders such as neointima formation after vascular injury, cardiac hypertrophy and myocardial infarction (MI). Recently, the biallelic polymorphism G + 1675A in intron 1 of the AT2 receptor gene has been associated with left ventricular posterior, septal and relative wall thickness, as well as left ventricular mass index in young hypertensive males.To investigate its potential role in left ventricular hypertrophy (LVH) and other cardiovascular traits, 1968 individuals from two population samples (the Glasgow Heart Scan, GLAECO and Glasgow Heart Scan Old, GLAOLD studies) with echocardiographically and electrocardiographically assessed phenotypes, were genotyped for G + 1675A using allele-specific oligonucleotide hybridization. Both studies had a similar design, only the age-ranges differed, being 25-74 years in the GLAECO study and 55-74 years in the GLAOLD study, so that internal consistency of results could also be assessed. Since the AT2 gene is located on the X chromosome, males and females were analysed separately.The + 1675A allele frequency was 0.49 and 0.51, in the GLAECO and GLAOLD studies, respectively. In both studies, the genotype frequencies were similar in hypertensive and non-hypertensive individuals. In the GLAOLD study, in females with episodes of coronary ischemia and MI, the AT2 + 1675A allele was more common than in females with no episode (86.5% vs. 73.5%, respectively; P0.007). This effect was not observed in males. In the same study, AT2 + 1675A allele carriers were more common in males with LVH, than in those without LVH (60.3% vs. 46.0%, respectively; P = 0.047). This result was unchanged after exclusion of subjects taking antihypertensive drugs (including ACE inhibitors) (64.4% vs. 47.4%, P = 0.038). However, in the GLAECO study, these results could not be replicated, even when subjects55 years of age were considered separately.Our study gives rise to a potential implication of the AT2 G + 1675A polymorphism in LVH and coronary ischemia subgroups. Since these results were not consistent in both studies, but are partially in agreement with two independent investigations, further efforts should be made to elucidate the specific nature of these genotype/phenotype interactions.

Aims The endothelin system plays a role in the complex pathophysiology of idiopathic dilated cardiomyopathy. We investigated whether genetic polymorphisms of the endothelin system might be associated with dilated cardiomyopathy-related cardiac phenotypes and differences in disease outcome. Methods One hundred and twenty-five unrelated dilated cardiomyopathy patients of a well characterized dilated cardiomyopathy cohort were genotyped for six common polymorphisms of the endothelin-1, endothelin-A (ETA) and endothelin-B (ETB) receptor genes using hybridization with allele-specific oligonucleotides. Results The H323H (C/T) polymorphism in exon 6 of the ETAreceptor gene was significantly associated with a shorter survival time after diagnosis. The odds ratio for carriers of the less frequent ETAT allele to die within 2 years after diagnosis was 5·5 (95% confidence interval, 1·4 to 21·0, P =0·013) compared to non-carriers. Kaplan–Meier analysis revealed a significantly different survival time for T allele carriers as compared to non-carriers as tested by logrank ( P =0·0196), Breslow ( P =0·0195), and Tarone tests ( P =0·020). The influence of the ETAH323H polymorphism on survival remained significant when known predictors of prognosis such as left ventricular ejection fraction, left ventricular end-diastolic diameter, age and NYHA functional classification were entered in a Cox proportional hazards analysis. In this model, end-diastolic diameter showed a trend to influence survival ( P =0·07) but only the ETAH323H polymorphism ( P =0·0029) was a significant independent predictor of survival. Conclusions Our results suggest that genetic variation in the ETAreceptor predicts survival in dilated cardiomyopathy patients, which might have important consequences for the identification of high-risk individuals.

In genome-wide studies, the intercellular adhesion molecule-1 (ICAM-1) locus has been associated with cardiovascular and inflammatory bowel diseases. To determine the functional relevance of five missense ICAM-1 variants (G241R; I316V; P352L; K469E; R478W), we generated wild-type and variant proteins [M2(241R); M3(469E); M4(352L); M5(478W); M6(316V); M7(352L/469E)] and transiently transfected CV1 cells. Reverse transcription PCR, western blot, and ELISA did not reveal any differences in mRNA and protein expression levels for any construct. Conversely, in pulse-chase experiments, compared with wild-type (90-120 min), M3 and M5 possessed a prolonged half-life of approximately 150 min, whereas M2, M4, and M7 displayed a decreased half-life of approximately 60-75 min, implying differences in protein degradation. Our results do not indicate a major impact of missense variants on ICAM-1 biological function, even if G241R and K469E were functional in pulse-chase experiments. Whether these differences in protein stability exert measurable functional consequences needs to be elucidated further.

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.

Body weight regulation is a complex phenotype also depending on the action of uncoupling proteins (UCPs) that mediate the "uncoupling" of respiration leading to the dissipation of energy as heat. This study investigated whether genetic variants in the genes encoding UCP-1 and UCP-3 are associated with different obesity-related phenotypes in 162 whites with a wide range of body mass index. All subjects were genotyped for the polymorphisms UCP-1 A-3826G, UCP-1 Ala64Thr, and UCP-3 C-55T using a PCR-based restriction method with appropriate enzymes. The frequencies of the UCP-1 3826G, UCP-1 64Thr, and UCP-3 55T alleles were 27.2%, 12.0%, and 22.8%, respectively. No significant associations were observed between polymorphism and body mass index or obesity. However, after adjustment for gender, age, body mass index, and diabetes mellitus the waist-to-hip ratio was significantly associated with UCP-1 Ala64Thr ( P=0.003) and UCP-3 C-55T ( P=0.02) but not with UCP-1 A-3826G. The higher waist-to-hip ratios associated with the UCP-1 64Thr and UCP-3 55T alleles were due to higher waist circumference in these allele carriers. In conclusion, central obesity in whites as reflected by an increased waist-to-hip ratio is associated with the UCP-1 Ala64Thr and UCP-3 C-55T polymorphisms. To what extent these genotypes contribute to the overall cardiovascular risk remains to be elucidated. ispartof: Journal of molecular medicine (Berlin, Germany) vol:81 issue:5 pages:327-32 ispartof: location:Germany status: published

Cathepsin G (CTSG), a serine protease released from activated neutrophils, may cause platelet activation, leading to intravascular thrombosis, thus contributing to cardiovascular and cerebrovascular disease. Applying the candidate gene approach, we screened the 5′-flanking region and the entire coding region of the CTSG gene for genetic variation by using polymerase chain reaction/single-strand conformation polymorphism analysis from 96 patients at high risk for myocardial infarction (MI). We identified 4 polymorphisms in the 5′-flanking region (G-618C, G-315A, C-179T, and C-160T) and 1 polymorphism in the coding region (Asn125Ser) of the gene and genotyped the participants in the Etude Cas-Temoins sur l’Infarctus du Myocarde (ECTIM Study), a case-control study for MI, and in the Étude du Profil Génétique de l’Infarctus Cérébral (GENIC Study), a case-control study for brain infarction (BI), for all identified genetic variants. The potential in vitro functionality of the 4 variants in the 5′-flanking region was investigated with transient transfection analyses in U937 cells with different allelic promoter constructs by using a luciferase assay. Our in vitro analyses did not reveal any differences for the investigated allelic constructs with respect to promoter activity, and none of the polymorphisms in the 5′-flanking region was associated with the available phenotypes in either study. Allele and genotype distributions of all identified polymorphisms did not globally differ between cases and controls in the ECTIM Study. However, in patients from the ECTIM Study, the Ser125 allele was significantly associated with elevated plasma fibrinogen levels ( P =0.006), but this effect was not seen in controls (case-control heterogeneity, P =0.04). There was a significant interaction between CTSG Asn125Ser and the β-fibrinogen gene polymorphism G-455A on plasma fibrinogen levels ( P =0.04). In the GENIC Study, the odds ratio for BI associated with CTSG Ser125 carrying was 1.82 (95% CI 1.16 to 2.84, P =0.008) in patients without a history of cardiovascular or cerebrovascular diseases. Our results indicate that the CTSG Ser125 allele is associated with plasma fibrinogen levels in MI patients from the ECTIM Study and with BI in the GENIC Study. Further studies should be carried out to define the underlying mechanisms.