@article {12, title = {ANGPTL3 Deficiency and Protection Against Coronary Artery Disease.}, journal = {J Am Coll Cardiol}, volume = {69}, year = {2017}, month = {2017 Apr 25}, pages = {2054-2063}, abstract = {

BACKGROUND: Familial combined hypolipidemia, a Mendelian condition characterized by substantial reductions in all 3~major lipid fractions, is caused by mutations that inactivate the gene angiopoietin-like 3 (ANGPTL3). Whether ANGPTL3 deficiency reduces risk of coronary artery disease (CAD) is unknown.

OBJECTIVES: The study goal was to leverage 3 distinct lines of evidence-a family that included individuals with complete (compound heterozygote) ANGPTL3 deficiency, a population based-study of humans with partial (heterozygote) ANGPTL3 deficiency, and biomarker levels in patients with myocardial infarction (MI)-to test whether ANGPTL3 deficiency is associated with lower risk for CAD.

METHODS: We assessed coronary atherosclerotic burden in 3 individuals with complete ANGPTL3 deficiency and 3~wild-type first-degree relatives using computed tomography angiography. In the population, ANGPTL3 loss-of-function (LOF) mutations were ascertained in up to 21,980 people with CAD and 158,200 control subjects. LOF mutations were~defined as nonsense, frameshift, and splice-site variants, along with missense variants resulting in~<25\% of wild-type ANGPTL3 activity in a mouse model. In a biomarker study, circulating ANGPTL3 concentration was measured in 1,493 people who presented with MI and 3,232 control subjects.

RESULTS: The 3 individuals with complete ANGPTL3 deficiency showed no evidence of coronary atherosclerotic plaque. ANGPTL3 gene sequencing demonstrated that approximately 1 in 309 people was a heterozygous carrier for an LOF mutation. Compared with those without mutation, heterozygous carriers of ANGPTL3 LOF mutations demonstrated a 17\% reduction in circulating triglycerides and a 12\% reduction in low-density lipoprotein cholesterol. Carrier status was associated with a 34\% reduction in odds of CAD (odds ratio: 0.66; 95\% confidence interval: 0.44 to 0.98; p~= 0.04). Individuals in the lowest tertile of circulating ANGPTL3 concentrations, compared with the highest, had reduced odds of MI (adjusted odds ratio: 0.65; 95\% confidence interval: 0.55 to 0.77; p~< 0.001).

CONCLUSIONS: ANGPTL3 deficiency is associated with protection from CAD.

}, keywords = {Adult, Angiopoietin-Like Protein 3, Angiopoietin-like Proteins, Angiopoietins, Animals, Atherosclerosis, Case-Control Studies, Coronary Artery Disease, Female, Humans, Lipids, Male, Mice, Inbred C57BL, Mice, Knockout, Middle Aged, Mutation, Missense, Myocardial Infarction, Risk Factors}, issn = {1558-3597}, doi = {10.1016/j.jacc.2017.02.030}, author = {Stitziel, Nathan O and Khera, Amit V and Wang, Xiao and Bierhals, Andrew J and Vourakis, A Christina and Sperry, Alexandra E and Natarajan, Pradeep and Klarin, Derek and Emdin, Connor A and Zekavat, Seyedeh M and Nomura, Akihiro and Erdmann, Jeanette and Schunkert, Heribert and Samani, Nilesh J and Kraus, William E and Shah, Svati H and Yu, Bing and Boerwinkle, Eric and Rader, Daniel J and Gupta, Namrata and Frossard, Philippe M and Rasheed, Asif and Danesh, John and Lander, Eric S and Gabriel, Stacey and Saleheen, Danish and Musunuru, Kiran and Kathiresan, Sekar} } @article {29, title = {Genetic association studies in cardiovascular diseases: Do we have enough power?}, journal = {Trends Cardiovasc Med}, volume = {27}, year = {2017}, month = {2017 Aug}, pages = {397-404}, abstract = {

Genetic association studies have a long history of delivering insightful results for cardiovascular disease (CVD) research. Beginning with early candidate gene studies, to genome-wide association studies, and now on to newer whole-genome sequencing studies, research in human genetics has enriched our understanding of the pathobiology of CVD. As these studies continue to expand, the issue of statistical power plays an important role in study design as well as the interpretation of results. We provide an overview of the component parts that determine statistical power and preview the future of CVD genetic association studies through this lens.

}, keywords = {Cardiovascular Diseases, Data Accuracy, Data Interpretation, Statistical, Genetic Association Studies, Genetic Markers, Genetic Predisposition to Disease, Genetic Variation, Humans, Phenotype, Reproducibility of Results, Research Design, Risk Assessment, Risk Factors}, issn = {1873-2615}, doi = {10.1016/j.tcm.2017.03.005}, author = {Auer, Paul L and Stitziel, Nathan O} } @article {21, title = {Polygenic Risk Score Identifies Subgroup With Higher Burden of Atherosclerosis and Greater Relative Benefit From Statin Therapy in the Primary Prevention Setting.}, journal = {Circulation}, volume = {135}, year = {2017}, month = {2017 May 30}, pages = {2091-2101}, abstract = {

BACKGROUND: Relative risk reduction with statin therapy has been consistent across nearly all subgroups studied to date. However, in analyses of 2 randomized controlled primary prevention trials (ASCOT [Anglo-Scandinavian Cardiac Outcomes Trial-Lipid-Lowering Arm] and JUPITER [Justification for the Use of Statins in Prevention: An Intervention Trial Evaluating Rosuvastatin]), statin therapy led to a greater relative risk reduction among a subgroup at high genetic risk. Here, we aimed to confirm this observation in a third primary prevention randomized controlled trial. In addition, we assessed whether those at high genetic risk had a greater burden of subclinical coronary atherosclerosis.

METHODS: We studied participants from a randomized controlled trial of primary prevention with statin therapy (WOSCOPS [West of Scotland Coronary Prevention Study]; n=4910) and 2 observational cohort studies (CARDIA [Coronary Artery Risk Development in Young Adults] and BioImage; n=1154 and 4392, respectively). For each participant, we calculated a polygenic risk score derived from up to 57 common DNA sequence variants previously associated with coronary heart disease. We compared the relative efficacy of statin therapy in those at high genetic risk (top quintile of polygenic risk score) versus all others (WOSCOPS), as well as the association between the polygenic risk score and coronary artery calcification (CARDIA) and carotid artery plaque burden (BioImage).

RESULTS: Among WOSCOPS trial participants at high genetic risk, statin therapy was associated with a relative risk reduction of 44\% (95\% confidence interval [CI], 22-60; <0.001), whereas in all others, the relative risk reduction was 24\% (95\% CI, 8-37; =0.004) despite similar low-density lipoprotein cholesterol lowering. In a study-level meta-analysis across the WOSCOPS, ASCOT, and JUPITER primary prevention, relative risk reduction in those at high genetic risk was 46\% versus 26\% in all others ( for heterogeneity=0.05). Across all 3 studies, the absolute risk reduction with statin therapy was 3.6\% (95\% CI, 2.0-5.1) among those in the high genetic risk group and 1.3\% (95\% CI, 0.6-1.9) in all others. Each 1-SD increase in the polygenic risk score was associated with 1.32-fold (95\% CI, 1.04-1.68) greater likelihood of having coronary artery calcification and 9.7\% higher (95\% CI, 2.2-17.8) burden of carotid plaque.

CONCLUSIONS: Those at high genetic risk have a greater burden of subclinical atherosclerosis and derive greater relative and absolute benefit from statin therapy to prevent a first coronary heart disease event.

CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00738725 (BioImage) and NCT00005130 (CARDIA). WOSCOPS was carried out and completed before the requirement for clinical trial registration.

}, keywords = {Adolescent, Adult, Aged, Aged, 80 and over, Atherosclerosis, Cohort Studies, Cost of Illness, Female, Humans, Hydroxymethylglutaryl-CoA Reductase Inhibitors, Male, Middle Aged, Multifactorial Inheritance, Primary Prevention, Risk Factors, Young Adult}, issn = {1524-4539}, doi = {10.1161/CIRCULATIONAHA.116.024436}, author = {Natarajan, Pradeep and Young, Robin and Stitziel, Nathan O and Padmanabhan, Sandosh and Baber, Usman and Mehran, Roxana and Sartori, Samantha and Fuster, Valentin and Reilly, Dermot F and Butterworth, Adam and Rader, Daniel J and Ford, Ian and Sattar, Naveed and Kathiresan, Sekar} }