Genetic Risk and Altering Lipids With Lifestyle Changes and Metformin: Is Fate Modifiable?

> It is not in the stars to hold our destiny but in ourselves > > —William Shakespeare The widespread availability and lower costs of genotyping and sequencing have resulted in the performance of a large number of genotype–phenotype association studies in cardiovascular medicine. The stringent requirements for correction for multiple testing and replication have particularly favored genotype–phenotype studies examining the association between genetic variation and quantitative traits that allows for greater statistical power. Multiple genome-wide association studies and a subsequent meta-analysis have identified >180 common and rare genetic variants associated with lipid traits.1,2 However, the effect size of these individual genetic variants is small, explaining only a small fraction of phenotypic variation prompting investigators to use genetic risk scores (GRS) that represent an aggregate of genetic risk to demonstrate clinical utility. Single-nucleotide polymorphisms (SNPs) and GRS have been used to predict cardiovascular disease such as coronary artery disease (CAD) and hypertension, surrogate markers of disease such as coronary calcium, cardiovascular outcomes such as myocardial infarction, and intermediate traits such as blood pressure and lipids.3 Article, see p 495 The Global Lipids Genetics Consortium has performed the largest genetic association study of lipid levels in 188 577 individuals from a total of 60 studies.1,2 There were 157 genetic loci that were identified, 95 were described previously and 62 were novel. The lipid level variance explained by the novel loci in this study ranged from 1.6% for high-density lipoprotein cholesterol (HDL-C) levels to 2.6% for total cholesterol levels. The total lipid variance explained by the previously described loci was 10% to 12%. The population studied was predominantly of European ancestry, and subjects on lipid-lowering therapy were excluded. The association of these genetic loci with lipid levels and a change in lipid levels with intervention in a prediabetic population …