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Background: Polygenic hazard scores (PHS) estimate age-dependent genetic risk of late-onset Alzheimer's disease (AD), but there is limited information about the performance of PHS on real-world data where the population of interest differs from the model development population and part of the model genotypes are missing or need to be imputed.Objective: The aim of this study was to estimate age-dependent risk of late-onset AD using polygenic predictors in Nordic populations.Methods: We used Desikan PHS model, based on Cox proportional hazards assumption, to obtain age-dependent hazard scores for AD from individual genotypes in the Norwegian DemGene cohort (n = 2,772). We assessed the risk discrimination and calibration of Desikan model and extended it by adding new genotype markers (the Desikan Nordic model). Finally, we evaluated both Desikan and Desikan Nordic models in two independent Danish cohorts: The Copenhagen City Heart Study (CCHS) cohort (n = 7,643) and The Copenhagen General Population Study (CGPS) cohort (n = 10,886).Results: We showed a robust prediction efficiency of Desikan model in stratifying AD risk groups in Nordic populations, even when some of the model SNPs were missing or imputed. We attempted to improve Desikan PHS model by adding new SNPs to it, but we still achieved similar risk discrimination and calibration with the extended model.Conclusion: PHS modeling has the potential to guide the timing of treatment initiation based on individual risk profiles and can help enrich clinical trials with people at high risk to AD in Nordic populations. [ABSTRACT FROM AUTHOR]

Context: Recent studies have discovered a role of apolipoprotein M (apoM) in energy metabolism, and observational analyses in humans suggest an association with type 2 diabetes. The causal relationship remains however elusive.Objective: To investigate whether reduced plasma apoM concentrations are causally linked to increased risk of type 2 diabetes.Design: Prospective study design analyzed by Mendelian randomization.Setting and Participants: Two cohorts reflecting the Danish general population: the Copenhagen City Heart Study (CCHS, n = 8589) and the Copenhagen General Population Study (CGPS; n = 93 857). Observational analyses included a subset of participants from the CCHS with available plasma apoM (n = 725). Genetic analyses included the complete cohorts (n = 102 446). During a median follow-up of 16 years (CCHS) and 8 years (CGPS), 563 and 2132 participants developed type 2 diabetes.Main Outcome Measures: Plasma apoM concentration, genetic variants in APOM, and type 2 diabetes.Results: First, we identified an inverse correlation between plasma apoM and risk of type 2 diabetes in a subset of participants from the CCHS (hazard ratio between highest vs lowest quartile (reference) = 0.32; 95% confidence interval = 0.1-1.01; P for trend = .02). Second, genotyping of specific single nucleotide polymorphisms in APOM further revealed a 10.8% (P = 6.2 × 10-5) reduced plasma apoM concentration in participants with variant rs1266078. Third, a meta-analysis including data from 599 451 individuals showed no association between rs1266078 and risk of type 2 diabetes.Conclusions: The present study does not appear to support a causal association between plasma apoM and risk of type 2 diabetes. [ABSTRACT FROM AUTHOR]

Genetic factors partly determine the risk for premature myocardial infarction (MI). We report the identification of a novel rare genetic variant in a kindred with an autosomal dominant trait for premature MI and atherosclerosis and explored the association of a common nonsynonymous variant in the same gene with the risk of ischemic heart disease (IHD) in a population-based study. Next-generation sequencing was performed in a small pedigree with premature MI or subclinical atherosclerosis. A common variant, rs8141797 A>G (p.Asn466Ser), in sushi domain–containing protein 2 (SUSD2) was studied in the prospective Copenhagen General Population Studies (N = 105,408) for association with IHD. A novel heterozygous nonsense mutation in SUSD2 (c.G583T; p.Glu195Ter) was associated with the disease phenotype in the pedigree. SUSD2 protein was expressed in aortic specimens in the subendothelial cell layer and around the vasa vasorum. Furthermore, the minor G-allele of rs8141797 was associated with per allele higher levels of SUSD2 mRNA expression in the heart and vasculature. In the Copenhagen General Population Study, hazard ratios for IHD were 0.92 (95% CI: 0.87–0.97) in AG heterozygotes and 0.86 (0.62–1.19) in GG homozygotes vs noncarrriers (P -trend =.002). Finally, in meta-analysis including 73,983 IHD cases and 215,730 controls, the odds ratio for IHD per G-allele vs A-allele was 0.93 (0.90–0.96) (P = 4.6 × 10−7). The identification of a truncating mutation in SUSD2 , which was associated with premature MI and subclinical atherosclerosis, combined with the finding that a common missense variant in SUSD2 was strongly associated with a lower risk of IHD, suggest that SUSD2 may alter the risk of atherosclerosis. • A nonsense mutation in sushi domain–containing protein 2 (SUSD2) was associated with the coronary artery disease phenotype in the family. • In meta-analysis, a common variant in SUSD2 was strongly associated with the risk of ischemic heart disease. • This suggests that SUSD2 may alter the risk of coronary artery disease. • Further experimental work in animal models is needed to support these observations. [ABSTRACT FROM AUTHOR]

Background: Reduced low-density lipoprotein (LDL) cholesterol due to inhibition of proprotein convertase subtilisin/kexin 9 (PCSK9) reduces cardiovascular events and may therefore also reduce cardiovascular and all-cause mortality.Objectives: This study tested the hypothesis that genetically low LDL cholesterol due to PCSK9 variation is causally associated with low cardiovascular and all-cause mortality in the general population.Methods: A total of 109,566 individuals from the Copenhagen General Population Study and the Copenhagen City Heart Study were genotyped for PCSK9 R46L (rs11591147), R237W (rs148195424), I474V (rs562556), and E670G (rs505151). During a median follow-up of 10 years (range 0 to 42 years) and 1,247,225 person-years, there were 3,828 cardiovascular deaths and 16,373 deaths from any cause. Results were validated using data on 431,043 individuals from the UK Biobank.Results: An increasing number of weighted PCSK9 alleles were associated with stepwise lower LDL cholesterol of up to 0.61 mmol/l (24 mg/dl; 18.2%; p for trend <0.001) and with lower cardiovascular mortality (p = 0.001), but not with lower all-cause mortality (p = 0.11). In causal, genetic analyses, a 0.5-mmol/l (19.4-mg/dl) lower LDL cholesterol was associated with risk ratios for cardiovascular and all-cause mortality of 0.79 (95% confidence interval [CI]: 0.63 to 0.99; p = 0.04) and 1.02 (95% CI: 0.94 to 1.12; p = 0.63) in the Copenhagen studies, 0.79 (95% CI: 0.58 to 1.08; p = 0.14) and 0.98 (95% CI: 0.87 to 1.10; p = 0.75) in the UK Biobank, and of 0.79 (95% CI: 0.65 to 0.95; p = 0.01) and 1.01 (95% CI: 0.94 to 1.08; p = 0.85), respectively, in studies combined.Conclusions: Genetically low LDL cholesterol due to PCSK9 variation was causally associated with low risk of cardiovascular mortality, but not with low all-cause mortality in the general population. [ABSTRACT FROM AUTHOR]

Elevated levels of lipoprotein(a) are associated with an increased risk of myocardial infarction. Our study aimed to test whether genetic data are consistent with this association being causal. Accordingly, we developed a high-throughput realtime PCR assay to genotype for the lipoprotein(a) kringle IV type 2 (KIV-2) repeat polymorphism in the LPA gene in > 40,000 individuals. The LPA KIV-2 genotype associated with plasma levels of lipoprotein(a) (trend p < 0.001), and the LPA KIV-2 genotype associated with risk of myocardial infarction (trend p < 0.001 to 0.03) in a manner consistent with its effect on plasma levels of lipoprotein(a). The association of LPA KIV-2 genotypes raising plasma levels of lipoprotein(a) with increased risk of myocardial infarction strongly supports a causal association of lipoprotein(a) with risk of myocardial infarction. [ABSTRACT FROM AUTHOR]

Elevated plasma levels of C-reactive protein (CRP), a marker of inflammation, are associated with an increased risk of cancer, but it is unclear whether this association is causal. We examined whether four common single-nucleotide polymorphisms (SNPs) in the CRP gene that are associated with altered plasma CRP levels are causally associated with an increased risk of cancer. The study population included participants in a prospective study (n = 10 215) and a cross-sectional study (n = 36 403) of the adult general population in Denmark, all of whom were genotyped for the CRP SNPs. The association between plasma CRP levels measured by a high-sensitivity turbidimetry assay and the risk of cancer was examined for 8224 participants in the prospective study. The hazard ratio of cancer for a doubling of the plasma CRP level was 1.09 (95% confidence interval [CI] = 1.03 to 1.14). The nine most common genotype combinations of the four CRP SNPs were associated with up to a 72% increase (95% CI = 58% to 87%) in CRP levels but not with an increased risk of cancer. The estimated causal odds ratio for cancer associated with a genetically induced doubling in CRP level was 0.94 (95% CI = 0.81 to 1.08). This finding suggests that elevated CRP levels do not cause cancer. [ABSTRACT FROM PUBLISHER]

We tested whether genetically elevated levels of C-reactive protein (CRP) cause increased risk of ischemic heart disease and ischemic cerebrovascular disease. Levels of CRP >3mg/L, compared with levels <1mg/L, associated with a 1.6- and 1.3-fold increased risk of ischemic heart disease and ischemic cerebrovascular disease. Genotype combinations of the 4 CRP polymorphisms associated with up to a 64% increase in CRP levels, resulting in a theoretically predicted increased risk of up to 32% for ischemic heart disease and up to 25% for ischemic cerebrovascular disease. However, these genotype combinations did not associate with increased risk of ischemic heart and cerebrovascular disease. [ABSTRACT FROM AUTHOR]

Background: Elevated levels of C-reactive protein (CRP) are associated with increased risks of ischemic heart disease and ischemic cerebrovascular disease. We tested whether this is a causal association. Methods: We studied 10,276 persons from a general population cohort, including 1786 in whom ischemic heart disease developed and 741 in whom ischemic cerebrovascular disease developed. We examined another 31,992 persons from a cross-sectional general population study, of whom 2521 had ischemic heart disease and 1483 had ischemic cerebrovascular disease. Finally, we compared 2238 patients with ischemic heart disease with 4474 control subjects and 612 patients with ischemic cerebrovascular disease with 1224 control subjects. We measured levels of high-sensitivity CRP and conducted genotyping for four CRP polymorphisms and two apolipoprotein E polymorphisms. Results: The risk of ischemic heart disease and ischemic cerebrovascular disease was increased by a factor of 1.6 and 1.3, respectively, in persons who had CRP levels above 3 mg per liter, as compared with persons who had CRP levels below 1 mg per liter. Genotype combinations of the four CRP polymorphisms were associated with an increase in CRP levels of up to 64%, resulting in a theoretically predicted increased risk of up to 32% for ischemic heart disease and up to 25% for ischemic cerebrovascular disease. However, these genotype combinations were not associated with an increased risk of ischemic vascular disease. In contrast, apolipoprotein E genotypes were associated with both elevated cholesterol levels and an increased risk of ischemic heart disease. Conclusions: Polymorphisms in the CRP gene are associated with marked increases in CRP levels and thus with a theoretically predicted increase in the risk of ischemic vascular disease. However, these polymorphisms are not in themselves associated with an increased risk of ischemic vascular disease. N Engl J Med 2008;359:1897-908. [ABSTRACT FROM AUTHOR]

Single nucleotide polymorphisms (SNPs) are hypothesized to explain the genetic predisposition to ischemic heart disease (IHD) in the general population. Lack of evidence for a role of such variation is fostering pessimism about the utility of genetic information in the practice of medicine. In this study we determined the utility of exonic and 5′ SNPs in apolipoprotein E ( APOE) and lipoprotein lipase ( LPL) when considered singly and in combination for predicting incidence of IHD in 8,456 individuals from the general population during 24 years of follow-up. In men, LPL D9N improved prediction of IHD ( P = 0.03) beyond smoking, diabetes and hypertension. The group of men heterozygous and homozygous for the rare D9N variant had a hazard ratio (HR) of 1.69 (95% confidence interval = 1.10–2.58) relative to the most common genotype. Pairwise combinations of D9N with −219G > T in APOE and N291S and S447X in LPL significantly improved the prediction of IHD ( P = 0.05 in women, P = 0.04 in men, P = 0.03 in men, respectively) beyond smoking, diabetes and hypertension, and identified subgroups of individuals ( n = 6–94) with highly significant HRs of 1.92–4.35. These results were validated in a case-control study ( n = 8,806). In conclusion, we present evidence that combinations of SNPs in APOE and LPL identify subgroups of individuals at substantially increased risk of IHD beyond that associated with smoking, diabetes and hypertension. [ABSTRACT FROM AUTHOR]

In the present study of 9,000 individuals representative of the general population, we have considered whether the addition of common single nucleotide polymorphisms (SNPs) in the promoter region ofApolipoprotein E(APOE) improve the statistical explanation of variation in lipid traits and test the hypothesis that the estimated genotype effects are independent of factors indexed by gender and age. To address these questions, we have asked, for each gender and for each 20-year age strata (young: 20-39 years; middle-aged: 40-59 years; old: 60-79 years; very old: 80-100 years), how much trait variation is associated with the traditional e2, e3, and e4 allelic variations defined by the g.2059T?C and g.2197C?T SNPs in the fourth exon of theAPOEgene, and how much additional trait variation is associated with genotypes defined by combining the g.2059T?C and g.2197C?T SNPs with one, two, or three promoter SNPs. Our study demonstrates that the pleiotropic effects of genotype variation defined by the traditional e2, e3, and e4 alleles on five plasma measures of lipid metabolism manifest differently in women and men and change significantly during the life cycle for high-density lipoprotein cholesterol in women. Multi-site genotypes defined by adding SNPs located in the 5' promoter region to the traditional g.2059T?C and g.2197C?T SNPs doubled the estimate of genetic variance of high-density lipoprotein and apolipoprotein Al in middle-aged females. [ABSTRACT FROM AUTHOR]

Studies the relationship between the risk of cancer and the homozygosity of the Leu33Pro polymorphism of the integrin beta[sub 3]. Genotyping by restriction fragment length polymorphism; Study population; Statistical analysis.

Discusses the investigation regarding the association between angiotensin-converting enzyme (ACE) gene polymorphism along with ischemic cerebrovascular disease. What is ACE involved in; Location of the ACE gene; Information on the tested hypothesis on the representation of the ACE gene polymorphism; Reference to the study conducted mentioning the participants involved.

Abstract: Ischemic cardiovascular disease and obstructive pulmonary disease involve inflammation. Leukotrienes may be important pro-inflammatory mediators. We tested the hypothesis that the (-1072)G>A and (-444)A>C promoter polymorphisms of leukotriene C4 synthase confer risk of transient ischemic attack (TIA), ischemic stroke, ischemic heart disease (IHD), asthma, and chronic obstructive pulmonary disease (COPD). We genotyped individuals from the Danish general population, the Copenhagen City Heart Study, and Danish patients with IHD/coronary atherosclerosis, the Copenhagen Ischemic Heart Disease Study. We used prospective (n =10,386), cross-sectional (n =10,386), and case-control (n =2392+5012) designs. Allele frequency was 0.07 for (-1072)A and 0.29 for (-444)C. Cumulative incidence for TIA was higher for (-1072)AA versus GG genotype (log-rank: p <0.001), and lower for (-444)CC versus AA genotype (log-rank: p =0.03). Cumulative incidence for ischemic stroke was also lower for (-444)CC versus AA genotype (log-rank: p =0.04). Multifactorially adjusted hazard ratios for TIA were 5.2(95% CI:1.9–14) for (-1072)AA versus GG genotype, and 0.4(0.2–1.0) for (-444)CC versus AA genotype. Corresponding values were 1.9 (0.7–5.2) and 0.7 (0.5–1.0) for ischemic stroke, and 0.8 (0.4–1.6) and 1.0 (0.9–1.2) for IHD. In the case-control study, corresponding multifactorially adjusted odds ratios for IHD/coronary atherosclerosis were 0.5 (0.2–1.3) and 1.2 (1.0–1.5). These genotypes were not associated with risk of asthma or COPD. Leukotriene C4 synthase promoter genotypes influence risk of TIA and ischemic stroke, but not risk of IHD/coronary atherosclerosis, asthma, or COPD. [Copyright &y& Elsevier]

Background: The high-density lipoprotein hypothesis of atherosclerosis has been challenged by clinical trials of cholesteryl ester transfer protein (CETP) inhibitors, which failed to show significant reductions in cardiovascular events. Plasma levels of high-density lipoprotein cholesterol (HDL-C) decline drastically during sepsis, and this phenomenon is explained, in part, by the activity of CETP, a major determinant of plasma HDL-C levels. We tested the hypothesis that genetic or pharmacological inhibition of CETP would preserve high-density lipoprotein levels and decrease mortality in clinical cohorts and animal models of sepsis.Methods: We examined the effect of a gain-of-function variant in CETP (rs1800777, p.Arg468Gln) and a genetic score for decreased CETP function on 28-day sepsis survival using Cox proportional hazard models adjusted for age and sex in the UK Biobank (n=5949), iSPAAR (Identification of SNPs Predisposing to Altered Acute Lung Injury Risk; n=882), Copenhagen General Population Study (n=2068), Copenhagen City Heart Study (n=493), Early Infection (n=200), St Paul's Intensive Care Unit 2 (n=203), and Vasopressin Versus Norepinephrine Infusion in Patients With Septic Shock studies (n=632). We then studied the effect of the CETP inhibitor, anacetrapib, in adult female APOE*3-Leiden mice with or without human CETP expression using the cecal-ligation and puncture model of sepsis.Results: A fixed-effect meta-analysis of all 7 cohorts found that the CETP gain-of-function variant was significantly associated with increased risk of acute sepsis mortality (hazard ratio, 1.44 [95% CI, 1.22-1.70]; P<0.0001). In addition, a genetic score for decreased CETP function was associated with significantly decreased sepsis mortality in the UK Biobank (hazard ratio, 0.77 [95% CI, 0.59-1.00] per 1 mmol/L increase in HDL-C) and iSPAAR cohorts (hazard ratio, 0.60 [95% CI, 0.37-0.98] per 1 mmol/L increase in HDL-C). APOE*3-Leiden.CETP mice treated with anacetrapib had preserved levels of HDL-C and apolipoprotein-AI and increased survival relative to placebo treatment (70.6% versus 35.3%, Log-rank P=0.03), whereas there was no effect of anacetrapib on the survival of APOE*3-Leiden mice that did not express CETP (50.0% versus 42.9%, Log-rank P=0.87).Conclusions: Clinical genetics and humanized mouse models suggest that inhibiting CETP may preserve high-density lipoprotein levels and improve outcomes for individuals with sepsis. [ABSTRACT FROM AUTHOR]

Objectives: The study sought to test the hypothesis that genetic variation in ABCG5/8, the transporter responsible for intestinal and hepatobiliary cholesterol efflux, may simultaneously influence plasma and biliary cholesterol levels, and hence risk of myocardial infarction (MI) and gallstone disease in opposite directions. Background: High plasma levels of low-density lipoprotein (LDL) cholesterol are a causal risk factor for MI, whereas high levels of biliary cholesterol promote gallstone formation. Methods: A total of 60,239 subjects from Copenhagen were included, including 5,647 with MI and 3,174 with symptomatic gallstone disease. Subjects were genotyped for 6 common, nonsynonymous and functional variants in ABCG5/8, and a combined weighted genotype score was calculated. Results: Combined, weighted genotype scores were associated with stepwise decreases in LDL cholesterol of up to 5.9% (0.20 mmol/l) for individuals with a score ≥8.0 (prevalence = 11%) versus <2.0 (prevalence = 9%; p for trend across 5 groups = 2 × 10E-35). The cumulative incidences of MI and gallstone disease as a function of age and increasing genotype score were decreased and increased (log-rank ps for trend: 6 × 10E-4 and 9 × 10E-45), respectively. The multifactorially adjusted odds ratios were 0.83 (95% confidence interval: 0.73 to 0.94) for MI and 2.85 (95% confidence interval: 2.39 to 3.39) for symptomatic gallstone disease for individuals with a genotype score ≥8.0 versus <2.0. Conclusions: Genetic variation in ABCG5/8, which associates with decreased levels of plasma LDL cholesterol protects against MI, but increases the risk of symptomatic gallstone disease. These results suggest that MI and gallstones, 2 seemingly unrelated diseases, are intrinsically linked via the function of the ABCG5/8 cholesterol transporter. [ABSTRACT FROM AUTHOR]

Objectives: This study was designed to test the hypotheses that single nucleotide polymorphisms (SNPs), in zinc finger protein 202 (ZNF202), predict severe atherosclerosis and ischemic heart disease (IHD). Background: ZNF202 is a transcriptional repressor controlling promoter elements in genes involved in vascular maintenance and lipid metabolism. Methods: We first determined genotype association for 9 ZNF202 SNPs with severe atherosclerosis (ankle brachial index >0.7 vs. ≤0.7) in a cross-sectional study of 5,355 individuals from the Danish general population. We then determined genotype association with IHD in 10,431 individuals from the Danish general population, the CCHS (Copenhagen City Heart Study), including 1,511 incident IHD events during 28 years of follow-up. Results were verified in 2 independent case-control studies including, respectively, 942 and 1,549 cases with IHD and 8,998 controls. Finally, we determined whether g.−660A>G altered transcriptional activity of the ZNF202 promoter in vitro. Results: Cross-sectionally, ZNF202 g.−660 GG versus AA homozygosity predicted an odds ratio for severe atherosclerosis of 2.01 (95% confidence interval [CI]: 1.34 to 3.01). Prospectively, GG versus AA homozygosity predicted a hazard ratio for IHD of 1.21 (95% CI: 1.02 to 1.43). In the 2 case-control studies, the equivalent odds ratios for IHD were 1.29 (95% CI: 1.02 to 1.62) and 1.60 (95% CI: 1.34 to 1.92), confirming the results from the prospective study. Only 2 other SNPs, which were highly correlated with g.−660A>G, also predicted risk of severe atherosclerosis and IHD. Finally, ZNF202 g.−660G versus g.−660A was associated with a 60% reduction in transcriptional activity in vitro, whereas none of the 2 correlated SNPs were predicted to be functional. Conclusions: Homozygosity for a common functional promoter variant in ZNF202 predicts severe atherosclerosis and an increased risk of IHD. [Copyright &y& Elsevier]

Homozygosity for mutations in ABC transporter A1 (ABCA1) causes Tangier disease, a rare HDL-deficiency syndrome. Whether heterozygosity for genetic variation in ABCA1 also contributes to HDL cholesterol (HDL-C) levels in the general population is presently unclear. We determined whether mutations or single-nucleotide polymorphisms (SNPs) in ABCA1 were overrepresented in individuals with the lowest 1% (n=95) or highest 1% (n=95) HDL-C levels in the general population by screening the core promoter and coding region of ABCA1. For all nonsynonymous SNPs identified, we determined the effect of genotype on lipid traits in 9,259 individuals from the general population. Heterozygosity for ABCA1 mutations was identified in 10% of individuals with low HDL-C only. Three of 6 nonsynonymous SNPs (V771M, V825I, and R1587K) were associated with increases or decreases in HDL-C in women in the general population and some with consistent trends in men, determined as isolated single-site effects varying only at the relevant SNP. Finally, these results were consistent over time. In conclusion, we show that at least 10% of individuals with low HDL-C in the general population are heterozygous for mutations in ABCA1 and that both mutations and SNPs in ABCA1 contribute to HDL-C levels in the general population. [ABSTRACT FROM AUTHOR]