Cholesteryl Ester Transfer Protein Variants Research Articles

Lower activity of cholesteryl ester transfer protein (CETP) and the risk of dementia: a Mendelian randomization analysis

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): New Amterdam Pharma Background Elevated levels of low-density lipoprotein cholesterol (LDL-C) are linked to dementia risk, and conversely, increased plasma concentrations of high-density lipoprotein cholesterol (HDL-C) and apolipoprotein-A1 (Apo-A1) associate with decreased dementia risk. Inhibition of cholesteryl ester transfer protein (CETP) meaningfully affects the concentrations of these blood lipids and may therefore provide an opportunity to treat dementia. Methods Drug target Mendelian randomization (MR) was employed to anticipate the on-target effects of lower CETP concentration (µg/mL) on plasma lipids, cardiovascular disease, Lewy body dementia (LBD), as well as Parkinson’s dementia. Replication was sought by performed Apo-A1 and Apo-B weighted MR analyses of CETP variants. Genetic associations with protein expression in cerebrospinal fluid (CSF) and brain were consulted to identify potential associations of plasma CETP with dementia implicated proteins. Results MR analysis of lower CETP concentration (per µg/mL) recapitulated the blood lipid effects observed in clinical trials of CETP-inhibitors, as well as protective effects on CHD (odds ratio (OR) 0.92, 95% confidence interval (CI) 0.89; 0.96), heart failure, abdominal aortic aneurysm any stroke, ischemic stroke, and small vessel stroke (0.90, 95%CI 0.85; 0.96); Figure. Consideration of dementia related traits indicated that lower CETP concentrations were associated higher total brain volume (0.04 per standard deviation, 95%CI 0.02; 0.06), lower risk of LBD (OR 0.81, 95%CI 0.74; 0.89) and Parkinson’s dementia risk (OR 0.26, 95%CI 0.14; 0.48). APOE4 stratified analyses suggested the LBD effect was most pronounced in APOE-ε4+ participants (OR 0.61 95%CI 0.51; 0.73), compared to APOE-ε4- (OR 0.89 95%CI 0.79; 1.01); interaction p-value 5.81×10-4. The aforementioned associations were replicated using Apo-B and Apo-A1 weighted analyses; Figure. Additionally, MR was employed to link plasma CETP concentration to the levels of CSF and brain proteins such as EPHA2 and CSF-1, which are in development as dementia drug targets. Conclusion These results suggest that inhibition of CETP may be a viable strategy to treat dementia.

Body mass index-dependent association between cholesteryl ester transfer protein variants and atherometabolic risk factors in gestational diabetes mellitus

Objective Gestational diabetes mellitus (GDM) is associated with metabolic abnormalities such as an altered serum lipid profile. This study investigated the influence of polymorphisms in the lipid metabolism-related cholesteryl ester transfer protein gene (CETP) on the metabolic parameters of pregnant women with GDM. Methods This prospective case-control study included 665 women with GDM and 1,044 women with uncomplicated pregnancies. The PCR-restriction fragment length polymorphism method was used to genotype rs708272 and rs1800775 single nucleotide polymorphisms (SNPs). Lipid and glucose metabolic parameters were assessed. Genetic associations with related traits were analyzed. Results Genotype distributions of rs708272 and rs1800775 in patients with GDM were similar to those in normal controls. However, the two CETP SNPs were associated with altered plasma total cholesterol (TC), high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol (LDL-C) concentrations in patients with GDM and in control pregnant women. Additional subgroup analysis demonstrated that the rs708272 polymorphism was associated with variations in triglyceride (TGs), TC, LDL-C, and apolipoprotein B (ApoB) levels in patients with overweight or obesity GDM, whereas both polymorphisms were associated with glucose metabolic traits (plasma insulin, glucose, or insulin) and the insulin resistance index in patients with GDM without obesity. Conclusions In patients with GDM, the rs708272 polymorphism was associated with atherogenic lipid levels (TG, TC, LDL-C, and ApoB), whereas the rs708272 and rs1800775 polymorphisms were associated with glucose metabolism and insulin resistance parameters, which were influenced by the body mass index. These results suggest that genetic associations with atherogenic metabolic factors may increase the risk of adverse outcomes in mothers with GDM and their offspring.

Variants in the CETP gene affect levels of HDL cholesterol by reducing the amount, and not the specific lipid transfer activity, of secreted CETP.

Cholesteryl ester transfer protein (CETP) transfers cholesteryl esters in plasma from high density lipoprotein (HDL) to very low density lipoprotein and low density lipoprotein. Loss-of-function variants in the CETP gene cause elevated levels of HDL cholesterol. In this study, we have determined the functional consequences of 24 missense variants in the CETP gene. The 24 missense variants studied were the ones reported in the Human Gene Mutation Database and in the literature to affect HDL cholesterol levels, as well as two novel variants identified at the Unit for Cardiac and Cardiovascular Genetics, Oslo University Hospital in subjects with hyperalphalipoproteinemia. HEK293 cells were transiently transfected with mutant CETP plasmids. The amounts of CETP protein in lysates and media were determined by Western blot analysis, and the lipid transfer activities of the CETP variants were determined by a fluorescence-based assay. Four of the CETP variants were not secreted. Five of the variants were secreted less than 15% compared to the WT-CETP, while the other 15 variants were secreted in varying amounts. There was a linear relationship between the levels of secreted protein and the lipid transfer activities (r = 0.96, p<0.001). Thus, the secreted variants had similar specific lipid transfer activities. The effect of the 24 missense variants in the CETP gene on the lipid transfer activity was mediated predominantly by their impact on the secretion of the CETP protein. The four variants that prevented CETP secretion cause autosomal dominant hyperalphalipoproteinemia. The five variants that markedly reduced secretion of the respective variants cause mild hyperalphalipoproteinemia. The majority of the remaining 15 variants had minor effects on the secretion of CETP, and are considered neutral genetic variants.

Comparing the drug target effects of Cholesteryl ester transfer protein (CETP) on cardiovascular diseases in East Asian and European populations

Abstract Introduction Cholesteryl ester transfer protein (CETP) is a drug target originally evaluated for raising HDL-C, for efficacy against coronary heart disease (CHD). Previous attempts to develop a licensed drug compound inhibiting CETP have heterogeneous CHD effects, which are likely attributable to the developed compound rather than CETP itself. Currently, novel CETP inhibitors are being pursued for the treatment of CHD. Drug target Mendelian randomization studies, leveraging genetic evidence, have shown that on-target CETP inhibition reduces CHD risk in individuals of European ancestries. However, similar MR studies conducted in East Asian ancestries have failed to show a CHD effect, questioning the value of pharmacological inhibition of CETP in this population. Purpose In this study, we compared drug target MR effects of CETP inhibition in Europeans and East Asians, focusing on cardiovascular efficacy outcomes, and relevant safety outcomes. Methods We used ancestry-specific GWAS summary statistics for Europeans (n=1,320,016) and East Asians (n=146,492) from the Global Lipids Genetics Consortium, taking variants from within and around ±50 kbp of the CETP locus. Colocalization was employed to determine potential trans-ancestry signals between CETP variants for HDL-C and LDL-C. Subsequently, drug target MR was used to estimate ancestry-specific effects of on-target CETP inhibition on 11 plasma biomarkers and 15 clinical outcomes between East Asian and European populations. Differences between ancestries were evaluated using interaction tests. Results There was strong support (posterior probability: 99.8%) of a shared causal CETP variant affecting HDL-C in both populations. Given the absence of a LDL-C signal in East Asians, similar colocalization was not observed for LDL-C. Employing drug target MR scaled to a standard deviation increase in HDL-C, we found that lower CETP had more pronounced decreasing effects in Europeans on LDL-C, LP[a], systolic blood pressure and pulse pressure (interaction p-values &amp;gt;1.9×10-3). Nevertheless, lower CETP protected against CHD, angina, intracerebral haemorrhage, and heart failure in both ancestries, for example for CHD (OR, 0.89; 95%CI, 0.84-0.94) in East Asians, compared to Europeans (OR, 0.95; 95%CI, 0.92-0.99, interaction p-value: 0.05). Exploring potential safety outcomes, lower CETP was protective against pneumonia in Europeans and East Asians (interaction p-value=0.53) and had a potential harmful effect on asthma and chronic kidney disease in East Asians (interaction p-value &amp;gt; 1.9×10-3). Conclusion In conclusion, on-target and sufficiently potent CETP inhibition is anticipated to prevent cardiovascular diseases in both European and East Asian populations.

Abstract 14019: Comparing the Effect Profile of CETP in Individuals of East Asian and European Ancestries

Introduction: Cholesteryl ester transfer protein (CETP) is a lipid drug target under development for CHD in both European and East Asian populations.Previous drug target Mendelian randomization (MR) studies conducted in East Asians failed to show a CHD effect, which has been interpreted as lack of effectiveness of CETP inhibition for CHD prevention in this population. Hypothesis: In this study, we inferred the effect of CETP inhibition in individuals of European and East Asian ancestries using drug target Mendelian randomization. Methods: We leveraged genetic associations of CETP variants with major blood lipid fractions for individuals of European (n=1,320,016) and East Asian (n=146,492) ancestries. Colocalization was employed to identify potential cross-ancestry signals of CETP variants for plasma concentrations of LDL-C or HDL-C. Drug target MR was used to estimate ancestry-specific effects of on-target CETP inhibition. Differences between ancestries were evaluated using interaction tests, applying a multiplicity corrected alpha of 1.9х10 -3 based on the 26 considered traits. Results: There was strong support (posterior probability=1.00) of a shared causal CETP variant affecting HDL-C in both populations, which was not observed for LDL-C. Employing drug target MR scaled to a standard deviation increase in HDL-C, we found that lower CETP was associated with lower LDL-C, Lp[a], systolic blood pressure and pulse pressure in both groups, but the effects were more pronounced in European individuals (interaction p-values &lt; 1.9х10-3). Lower CETP was protective against CHD, angina, intracerebral haemorrhage and heart failure in both ancestries, for example for CHD in East Asians (OR 0.89, 95%CI 0.84;0.94) compared to Europeans (OR 0.95, 95%CI 0.92;0.99, interaction p-value=0.05). Conclusions: In conclusion, on-target inhibition of CETP is anticipated to decrease cardiovascular disease in individuals of both European and East Asian ancestries.

Impact of Lipid Genetic Risk Score and Saturated Fatty Acid Intake on Central Obesity in an Asian Indian Population.

Abnormalities in lipid metabolism have been linked to the development of obesity. We used a nutrigenetic approach to establish a link between lipids and obesity in Asian Indians, who are known to have a high prevalence of central obesity and dyslipidaemia. A sample of 497 Asian Indian individuals (260 with type 2 diabetes and 237 with normal glucose tolerance) (mean age: 44 ± 10 years) were randomly chosen from the Chennai Urban Rural Epidemiological Study (CURES). Dietary intake was assessed using a previously validated questionnaire. A genetic risk score (GRS) was constructed based on cholesteryl ester transfer protein (CETP) and lipoprotein lipase (LPL) genetic variants. There was a significant interaction between GRS and saturated fatty acid (SFA) intake on waist circumference (WC) (Pinteraction = 0.006). Individuals with a low SFA intake (≤23.2 g/day), despite carrying ≥2 risk alleles, had a smaller WC compared to individuals carrying <2 risk alleles (Beta = −0.01 cm; p = 0.03). For those individuals carrying ≥2 risk alleles, a high SFA intake (>23.2 g/day) was significantly associated with a larger WC than a low SFA intake (≤23.2 g/day) (Beta = 0.02 cm, p = 0.02). There were no significant interactions between GRS and other dietary factors on any of the measured outcomes. We conclude that a diet low in SFA might help reduce the genetic risk of central obesity confirmed by CETP and LPL genetic variants. Conversely, a high SFA diet increases the genetic risk of central obesity in Asian Indians.

The loss-of-function mutation of CETP affects HDLc levels but not ApoA1 in patients with acute myocardial infarction

Background and aimsLoss of the cholesteryl ester transfer protein (CETP) function affects HDLc levels, but its effects on major HDL protein component ApoA1 are not well understood in patients with acute myocardial infarction (AMI). Methods and resultsWe investigated the effects of an East Asian loss-of-function variant (rs2303790; p.D442G) in CETP gene on HDLc and ApoA1 levels and its relationship with AMI. A total of 2327 AMI patients and 2615 age- and sex-matched controls from INTERHEART-China study were included. In controls, both levels of HDLc (1.24 vs. 1.04 mmol/L, P = 0.001) and ApoA1 (1.48 vs. 1.37 mmol/L, P = 0.042) were significantly higher in CETP variant G allele carriers compared to CETP wildtype D allele carriers. In AMI patients, levels of HDLc were significantly higher (1.14 vs. 1.01 mmol/L, P = 0.013) while levels of ApoA1 were not statistically difference (1.31 vs. 1.32 mmol/L, P = 0.468) in CETP variant group compared to CETP wildtype group. Moreover, CETP variant is associated with HDLc increase, but is not associated with AMI risk (P = 0.564), even after adjusting for age, sex, history of hypertension and diabetes, waist to hip ratio, smoking, total cholesterol, LDL cholesterol, triglycerides, physical activity, depression, alcohol, vegetables and fruit consumption. ConclusionsLoss of CETP function is associated with increased HDLc and ApoA1 levels in healthy subjects, and in AMI patients, it is associated with HDLc levels but not ApoA1 levels. The lack of association of CETP variant with AMI may be related to the inability to increase ApoA1 levels and warranted further studies.

Cholesteryl Ester Transfer Protein Genetic Variants Associated with Risk for Type 2 Diabetes and Diabetic Kidney Disease in Taiwanese Population.

Cholesteryl ester transfer protein (CETP) plays an important role in lipid metabolism. Low levels of high-density lipoprotein cholesterol (HDL-C) increase the risk of type 2 diabetes (T2D). This study investigated CETP gene variants to assess the risk of T2D and specific complications of diabetic kidney disease (DKD) and diabetic retinopathy. Towards this, a total of 3023 Taiwanese individuals (1383 without T2D, 1640 with T2D) were enrolled in this study. T2D mice (+Leprdb/+Leprdb, db/db) were used to determine CETP expression in tissues. The A-alleles of rs3764261, rs4783961, and rs1800775 variants were found to be independently associated with 2.86, 1.71, and 0.91 mg/dL increase in HDL-C per allele, respectively. In addition, the A-allele of rs4783961 was significantly associated with a reduced T2D risk (odds ratio (OR), 0.82; 95% confidence interval (CI), 0.71–0.96)), and the A-allele of rs1800775 was significantly related to a lowered DKD risk (OR, 0.78; 95% CI, 0.64–0.96). CETP expression was significantly decreased in the T2D mice kidney compared to that in the control mice (T2D mice, 0.16 ± 0.01 vs. control mice, 0.21 ± 0.02; p = 0.02). These collective findings indicate that CETP variants in the promoter region may affect HDL-C levels. Taiwanese individuals possessing an allele associated with higher HDL-C levels had a lower risk of T2D and DKD.

Cholesteryl Ester Transfer Protein Variant (RS1800777) with Liver Histology in Non-Alcoholic Fatty Liver Disease Patients

Introduction and Aims: Non-alcoholic fatty liver disease (NAFLD) is a spectrum of diseases ranging from simple steatosis without inflammation or fibrosis to nonalcoholic steatohepatitis and in the Western countries has become one of the most prevalent chronic liver diseases related to metabolic and lipid alterations. Cholesteryl ester transfer protein (CETP) participates in high density lipoprotein (HDL)-cholesterol metabolism. The aim of our study was to investigate the influence of polymorphism (rs1800777) of CETP gene on liver histological changes, biochemical parameters, and serum adipokines levels in patients with NAFLD. Material and Methods: A population of 90 patients with NAFLD was recruited in a cross-sectional study. A biochemical analysis (glucose, c-reactive protein, insulin, homeostasis model assessment-insulin resistance, total cholesterol, low density lipoprotein (LDL)-cholesterol, HDL-cholesterol, triglycerides blood, and adipokines (leptin, adiponectin, and resistin) was realized. Genotype of polymorphism (rs1800777) of CETP gene was studied. Results: Eighty-three patients (92.2%) had the genotype GG (wild type group) and 7 patients (7.8%) had the genotype GA (n = 7) or AA (n = 0; mutant type group). Patients with A allele show significant decrease in liver biochemistry parameters – Alanine amino transferase (delta 10.1 ± 9.9 UI/L; p = 0.01), aspartate aminotransferase activity (delta 13.3 ± 9.5 UI/L; p = 0.02), and gammaglutamine transferase levels (delta 39 ± 30.1 UI/L; p = 0.01). Logistic regression analysis indicated that subjects with A-allele carriers were associated with a decreased risk of lobulillar inflammation (OR 0.18, 95% CI 0.04–0.95, p = 0.04) and a decreased risk of steatosis (OR 0.13, 95% CI 0.02–0.89, p = 0.04). Conclusions: A variant of the polymorphism rs1800777 of CETP gene is independently associated with the presence of steatosis and lobulillar inflammation in subjects with proven biopsy NAFLD.

Association of a cholesteryl ester transfer protein variant (rs1800777) with fat mass, HDL cholesterol levels, and metabolic syndrome

BackgroundThere is little evidence of the association between CETP SNPs and obesity and/or related metabolic parameters. ObjectiveTo analyze the association of the polymorphism rs1800777 of the CETP gene with anthropometric parameters, lipid profile, metabolic syndrome and its components, and adipokine levels in obese subjects without type 2 diabetes mellitus or hypertension. DesignA population of 1005 obese subjects was analyzed. Electrical bioimpedance was performed, and blood pressure, presence of metabolic syndrome, dietary intake, physical activity, and biochemical tests were recorded. ResultsNine hundred and sixty eight patients (96.3%) had the GG genotype, 37 patients the GA genotype (3.7%) (no AA genotype was detected). Fat mass (delta: 4.4±1.1kg; p=0.04), waist circumference (delta: 5.6±2.1cm; p=0.02), and waist to hip ratio (delta: 0.04±0.01cm; p=0.01) were higher in A allele carriers than in non-A allele carriers. HDL cholesterol levels were lower in A allele carriers than in non-A allele carriers (delta: 4.2±1.0mg/dL; p=0.04). In the logistic regression analysis, the GA genotype was associated to an increased risk of central obesity (OR 7.55, 95% CI 1.10–55.70, p=0.02) and low HDL cholesterol levels (OR 2.46, 95% CI 1.23–4.91, p=0.014). ConclusionThe CETP variant at position +82 is associated to lower HDL cholesterol levels, increased fat mass, and central obesity in obese subjects. These results may suggest a potential role of this variant gene in pathophysiology of adipose tissue.

Association of a cholesteryl ester transfer protein variant (rs1800777) with fat mass, HDL cholesterol levels, and metabolic syndrome

BackgroundThere is little evidence of the association between CETP SNPs and obesity and/or related metabolic parameters. ObjectiveTo analyze the association of the polymorphism rs1800777 of the CETP gene with anthropometric parameters, lipid profile, metabolic syndrome and its components, and adipokine levels in obese subjects without type 2 diabetes mellitus or hypertension. DesignA population of 1005 obese subjects was analyzed. Electrical bioimpedance was performed, and blood pressure, presence of metabolic syndrome, dietary intake, physical activity, and biochemical tests were recorded. ResultsNine hundred and sixty eight patients (96.3%) had the GG genotype, 37 patients the GA genotype (3.7%) (no AA genotype was detected). Fat mass (delta: 4.4±1.1kg; p=0.04), waist circumference (delta: 5.6±2.1cm; p=0.02), and waist to hip ratio (delta: 0.04±0.01cm; p=0.01) were higher in A allele carriers than in non-A allele carriers. HDL cholesterol levels were lower in A allele carriers than in non-A allele carriers (delta: 4.2±1.0mg/dL; p=0.04). In the logistic regression analysis, the GA genotype was associated to an increased risk of central obesity (OR 7.55, 95% CI 1.10–55.70, p=0.02) and low HDL cholesterol levels (OR 2.46, 95% CI 1.23–4.91, p=0.014). ConclusionThe CETP variant at position +82 is associated to lower HDL cholesterol levels, increased fat mass, and central obesity in obese subjects. These results may suggest a potential role of this variant gene in pathophysiology of adipose tissue.

Association of CETP Gene Variants With Risk for Vascular and Nonvascular Diseases Among Chinese Adults

Increasing levels of high-density lipoprotein (HDL) cholesterol through pharmacologic inhibition of cholesteryl ester transfer protein (CETP) is a potentially important strategy for prevention and treatment of cardiovascular disease (CVD). To use genetic variants in the CETP gene to assess potential risks and benefits of lifelong lower CETP activity on CVD and other outcomes. This prospective biobank study included 151 217 individuals aged 30 to 79 years who were enrolled from 5 urban and 5 rural areas of China from June 25, 2004, through July 15, 2008. All participants had baseline genotype data, 17 854 of whom had lipid measurements and 4657 of whom had lipoprotein particle measurements. Median follow-up of 9.2 years (interquartile range, 8.2-10.1 years) was completed January 1, 2016, through linkage to health insurance records and death and disease registries. Five CETP variants, including an East Asian loss-of-function variant (rs2303790), combined in a genetic score weighted to associations with HDL cholesterol levels. Baseline levels of lipids and lipoprotein particles, cardiovascular risk factors, incidence of carotid plaque and predefined major vascular and nonvascular diseases, and a phenome-wide range of diseases. Among the 151 217 individuals included in this study (58.4% women and 41.6% men), the mean (SD) age was 52.3 (10.9) years. Overall, the mean (SD) low-density lipoprotein (LDL) cholesterol level was 91 (27) mg/dL; HDL cholesterol level, 48 (12) mg/dL. CETP variants were strongly associated with higher concentrations of HDL cholesterol (eg, 6.1 [SE, 0.4] mg/dL per rs2303790-G allele; P = 9.4 × 10-47) but were not associated with lower LDL cholesterol levels. Within HDL particles, cholesterol esters were increased and triglycerides reduced, whereas within very low-density lipoprotein particles, cholesterol esters were reduced and triglycerides increased. When scaled to 10-mg/dL higher levels of HDL cholesterol, the CETP genetic score was not associated with occlusive CVD (18 550 events; odds ratio [OR], 0.98; 95% CI, 0.91-1.06), major coronary events (5767 events; OR, 1.08; 95% CI, 0.95-1.22), myocardial infarction (3118 events; OR, 1.14; 95% CI, 0.97-1.35), ischemic stroke (13 759 events; OR, 0.94; 95% CI, 0.86-1.02), intracerebral hemorrhage (6532 events; OR, 0.94; 95% CI, 0.83-1.06), or other vascular diseases or carotid plaque. Similarly, rs2303790 was not associated with any vascular diseases or plaque. No associations with nonvascular diseases were found other than an increased risk for eye diseases with rs2303790 (4090 events; OR, 1.43; 95% CI, 1.13-1.80; P = .003). CETP variants were associated with altered HDL metabolism but did not lower LDL cholesterol levels and had no significant association with risk for CVD. These results suggest that in the absence of reduced LDL cholesterol levels, increasing HDL cholesterol levels by inhibition of CETP may not confer significant benefits for CVD.

HDL and atherosclerotic cardiovascular disease: genetic insights into complex biology

Plasma levels of HDL cholesterol (HDL-C) predict the risk of cardiovascular disease at the epidemiological level, but a direct causal role for HDL in cardiovascular disease remains controversial. Studies in animal models and humans with rare monogenic disorders link only particular HDL-associated mechanisms with causality, including those mechanisms related to particle functionality rather than cholesterol content. Mendelian randomization studies indicate that most genetic variants that affect a range of pathways that increase plasma HDL-C levels are not usually associated with reduced risk of cardiovascular disease, with some exceptions, such as cholesteryl ester transfer protein variants. Furthermore, only a fraction of HDL-C variation has been explained by known loci from genome-wide association studies (GWAS), suggesting the existence of additional pathways and targets. Systems genetics can enhance our understanding of the spectrum of HDL pathways, particularly those pathways that involve new and non-obvious GWAS loci. Bioinformatic approaches can also define new molecular interactions inferred from both large-scale genotypic data and RNA sequencing data to reveal biologically meaningful gene modules and networks governing HDL metabolism with direct relevance to disease end points. Targeting these newly recognized causal networks might inform the development of novel therapeutic strategies to reduce the risk of cardiovascular disease.

Genetic variants in CETP increase risk of intracerebral hemorrhage.

ObjectiveIn observational epidemiologic studies, higher plasma high‐density lipoprotein cholesterol (HDL‐C) has been associated with increased risk of intracerebral hemorrhage (ICH). DNA sequence variants that decrease cholesteryl ester transfer protein (CETP) gene activity increase plasma HDL‐C; as such, medicines that inhibit CETP and raise HDL‐C are in clinical development. Here, we test the hypothesis that CETP DNA sequence variants associated with higher HDL‐C also increase risk for ICH.MethodsWe performed 2 candidate‐gene analyses of CETP. First, we tested individual CETP variants in a discovery cohort of 1,149 ICH cases and 1,238 controls from 3 studies, followed by replication in 1,625 cases and 1,845 controls from 5 studies. Second, we constructed a genetic risk score comprised of 7 independent variants at the CETP locus and tested this score for association with HDL‐C as well as ICH risk.ResultsTwelve variants within CETP demonstrated nominal association with ICH, with the strongest association at the rs173539 locus (odds ratio [OR] = 1.25, standard error [SE] = 0.06, p = 6.0 × 10−4) with no heterogeneity across studies (I 2 = 0%). This association was replicated in patients of European ancestry (p = 0.03). A genetic score of CETP variants found to increase HDL‐C by ∼2.85mg/dl in the Global Lipids Genetics Consortium was strongly associated with ICH risk (OR = 1.86, SE = 0.13, p = 1.39 × 10−6).InterpretationGenetic variants in CETP associated with increased HDL‐C raise the risk of ICH. Given ongoing therapeutic development in CETP inhibition and other HDL‐raising strategies, further exploration of potential adverse cerebrovascular outcomes may be warranted. Ann Neurol 2016;80:730–740

Fine mapping the CETP region reveals a common intronic insertion associated to HDL-C.

Background:Individuals with exceptional longevity and their offspring have significantly larger high-density lipoprotein concentrations (HDL-C) particle sizes due to the increased homozygosity for the I405V variant in the cholesteryl ester transfer protein (CETP) gene. In this study, we investigate the association of CETP and HDL-C further to identify novel, independent CETP variants associated with HDL-C in humans.Methods:We performed a meta-analysis of HDL-C within the CETP region using 59,432 individuals imputed with 1000 Genomes data. We performed replication in an independent sample of 47,866 individuals and validation was done by Sanger sequencing.Results:The meta-analysis of HDL-C within the CETP region identified five independent variants, including an exonic variant and a common intronic insertion. We replicated these 5 variants significantly in an independent sample of 47,866 individuals. Sanger sequencing of the insertion within a single family confirmed segregation of this variant. The strongest reported association between HDL-C and CETP variants, was rs3764261; however, after conditioning on the five novel variants we identified the support for rs3764261 was highly reduced (βunadjusted=3.179 mg/dl (P value=5.25×10−509), βadjusted=0.859 mg/dl (P value=9.51×10−25)), and this finding suggests that these five novel variants may partly explain the association of CETP with HDL-C. Indeed, three of the five novel variants (rs34065661, rs5817082, rs7499892) are independent of rs3764261.Conclusions:The causal variants in CETP that account for the association with HDL-C remain unknown. We used studies imputed to the 1000 Genomes reference panel for fine mapping of the CETP region. We identified and validated five variants within this region that may partly account for the association of the known variant (rs3764261), as well as other sources of genetic contribution to HDL-C.

CETP/LPL/LIPC gene polymorphisms and susceptibility to age-related macular degeneration.

Three high-density lipoprotein (HDL)-related loci have been reported to be associated with age-related macular degeneration (AMD), but the results were inconsistent. In this study, the cholesteryl ester transfer protein (CETP) rs3764261 variant was significantly associated with an increased risk of AMD (odds ratio [OR] = 1.13, 95% confidence interval [CI]: 1.05–1.21, P < 0.001), and the hepatic lipase (LIPC) rs10468017 variant was associated with a significantly decreased risk of AMD (OR = 0.81, CI: 0.76–0.86, P < 0.001). Individuals carrying the lipoprotein lipase (LPL) rs12678919 polymorphism (A → G) had no significant change in the risk of developing AMD (OR = 1.01, CI: 0.92–1.10, P = 0.17). After adjusting for the complement factor H (CFH) gene, both CETP and LPL conferred a significantly increased AMD risk (ORCETP = 1.17, CI: 1.08–1.26, P < 0.001; ORLPL = 1.11, CI: 1.01–1.22, P = 0.02). Subgroup analysis based on ethnicity revealed a significant association between the CETP variant and AMD in both Americans (OR = 1.12, CI: 1.02–1.23, P = 0.01) and Europeans (OR = 1.10, CI: 1.01–1.19, P = 0.011). This meta-analysis revealed that both CETP rs3764261 and LIPC rs10468017 polymorphisms were significantly associated with AMD risk. After adjustment for the CFH gene, CETP/LPL conferred a significantly increased susceptibility to the disease, indicating potential interactions among genes in the complement system and the lipid metabolism pathway.

CETP genotype and changes in lipid levels in response to weight-loss diet intervention in the POUNDS LOST and DIRECT randomized trials

Little is known about whether cholesteryl ester transfer protein (CETP) genetic variation may modify the effect of weight-loss diets varying in fat content on changes in lipid levels. We analyzed the interaction between the CETP variant rs3764261 and dietary interventions on changes in lipid levels among 732 overweight/obese adults from a 2 year randomized weight-loss trial [Preventing Overweight Using Novel Dietary Strategies (POUNDS LOST)], and replicated the findings in 171 overweight/obese adults from an independent 2 year weight-loss trial [Dietary Intervention Randomized Controlled Trial (DIRECT)]. In the POUNDS LOST, participants with the CETP rs3764261 CC genotype on the high-fat diet had larger increases in HDL cholesterol (P = 0.001) and decreases in triglycerides (P = 0.007) than those on the low-fat diet at 6 months, while no significant difference between these two diets was observed among participants carrying other genotypes. The gene-diet interactions on changes in HDL-cholesterol and tri-glyc-erides were replicated in the DIRECT (pooled P for interaction ≤ 0.01). Similar results on trajectory of changes in HDL cholesterol and triglycerides over the 2 year intervention were observed in both trials. Our study provides replicable evidence that individuals with the CETP rs3764261 CC genotype might derive greater effects on raising HDL cholesterol and lowering triglycerides by choosing a low-carbohydrate/high-fat weight-loss diet instead of a low-fat diet.

Cholesteryl Ester Transfer Protein Polymorphisms, Statin Use, and Their Impact on Cholesterol Levels and Cardiovascular Events

The association of nonfunctional variants of the cholesteryl ester transfer protein (CETP) with efficacy of statins has been a subject of debate. We evaluated whether three functional CETP variants influence statin efficacy. The effect of CETP genotype on achieved levels of high-density lipoprotein cholesterol (HDLc), low-density lipoprotein cholesterol (LDLc), and total cholesterol during statin treatment was estimated by meta-analysis of the linear regression outcomes of three studies (11,021 individuals). The effect of these single-nucleotide polymorphisms (SNPs) on statin response in protecting against myocardial infarction (MI) was estimated by meta-analysis of statin × SNP interaction terms from logistic regression in five studies (16,570 individuals). The enhancer SNP rs3764261 significantly increased HDLc by 0.02 mmol/l per T allele (P = 6 × 10(-5)) and reduced protection against MI by statins (interaction odds ratio (OR) = 1.19 per T allele; P = 0.04). Focusing on functional CETP variants, we showed that in carriers of the rs3764261 T variant, HDLc increased more during statin treatment, and protection against MI by statins appeared to be reduced as compared with those in noncarriers.

Single Nucleotide Polymorphisms in Cholesteryl Ester Transfer Protein Gene and Recurrent Coronary Heart Disease or Mortality in Patients With Established Atherosclerosis

It is not known whether genetic variants in the cholesteryl ester transfer protein (CETP) gene are associated with recurrent coronary heart disease events or mortality in secondary prevention patients. Among 3,717 patients with acute coronary syndrome or coronary artery bypass grafting (CABG) enrolled in a prospective genetic registry, we evaluated whether CETP gene variants previously shown to be associated with reduced CETP activity and high-density lipoprotein cholesterol increase ("A" allele for both TaqIB [rs708272] and rs12149545) are associated with a reduction in recurrent myocardial infarction (MI), recurrent revascularization, or death. At 4.5years of follow-up, 439 recurrent MI, 698 recurrent revascularizations, and 756 deaths occurred. Using an additive model of inheritance, the "A" allele for rs708272 was not associated with recurrent MI (hazard ratio [HR] 0.95, 95% confidence interval [CI] 0.78 to 1.17 for AG; HR 0.89, 95% CI 0.67 to 1.19 for AA; compared with GG genotype), recurrent revascularization (HR 1.13, 95% CI 0.95 to 1.33 for AG; HR 1.05, 95% CI 0.84 to 1.32 for AA), or mortality (HR 1.02, 95% CI 0.86 to 1.19 for AG; HR 1.11, 95% CI 0.91 to 1.37 for AA) in the overall cohort. Similar results were seen for the "A" allele for rs12149545. In the CABG subgroup, AG genotype for rs708272 was associated with an increased mortality (HR 1.38, 95% CI 1.06 to 1.79) compared with GG genotype. Results remained consistent using dominant model of inheritance. In conclusion, genetic CETP variants were not associated with recurrent MI or recurrent revascularization in overall cohort with a possible mortality increase in patients who underwent CABG.

Cholesteryl Ester Transfer Protein and ATP-Binding Cassette Transporter A1 Genotype Alter the Atorvastatin and Simvastatin Efficacy

We compared the efficacy of atorvastatin with simvastatin according to cholesteryl ester transfer protein (CETP) and adenosine triphosphate-binding cassette transporter A1 (ABCA1) genes. Patients treated with atorvastatin (n = 254) or simvastatin (n = 332) were genotyped for CETP (TaqIB and I405V) and ABCA1 (R219K) genetic variants. For genotype B1B2, atorvastatin compared with simvastatin treatment resulted in a greater decrease in total cholesterol (35.4% vs 31.6%, P = .035) and a lower increase in high-density lipoprotein cholesterol (2% vs 8%, P = .05). For genotype B2B2, atorvastatin compared with simvastatin treatment resulted in a lower decrease in low-density lipoprotein cholesterol (31.85 vs 42%, P = .029). For genotypes RR and KK, atorvastatin compared with simvastatin treatment resulted in a greater decrease of triglycerides (27% vs 17% and 35% vs 15%, respectively; P = .02 for all comparisons). The TaqIB and R219K (opposite to I405V) gene polymorphisms seem to modify the response to lipid-lowering therapy with simvastatin or atorvastatin treatment.