The I405V and Taq1B polymorphisms of the CETP gene differentially affect sub-clinical carotid atherosclerosis

Mendelian randomization analysis of cholesteryl ester transfer protein and subclinical atherosclerosis: A population-based study

BACKGROUND

Several trials to prevent cardiovascular disease by inhibiting cholesteryl ester transfer protein (CETP) have failed, except Randomized EValuation of the Effects of Anacetrapib through Lipid-modification. Thus far, it is unclear to what extent CETP is causally related to measures of atherosclerosis.

OBJECTIVE

The aim of the article was to study the causal relationship between genetically determined CETP concentration and carotid intima-media thickness (cIMT) in a population-based cohort study.

METHODS

In the Netherlands Epidemiology of Obesity study, participants were genotyped, and cIMT was measured by ultrasonography. We examined the relation between a weighted genetic risk score for CETP concentration, based on 3 single-nucleotide polymorphisms that have previously been shown to largely determine CETP concentration and cIMT using Mendelian randomization in the total population and in strata by sex, Framingham 10-year risk, (pre)diabetes, high-density lipoprotein cholesterol, triglycerides, and statin use.

RESULTS

We analyzed 5655 participants (56% women) with a mean age of 56 (range 44-66) years, body mass index of 26 (range 17-61) kg/m², and serum CETP of 2.47 (range 0.68-5.33) μg/mL. There was no evidence for a causal relation between genetically determined CETP and cIMT in the total population, but associations were differently directed in men (16 μm per μg/mL increase in genetically determined CETP; 95% confidence interval: -8, 39) and women (-8 μm; -25, 9). Genetically determined CETP appeared to be associated with cIMT in normoglycemic men (26 μm; -1, 52) and in (pre)diabetic women (48 μm; -2, 98).

CONCLUSION

In this population-based study, there was no causal relation between genetically determined CETP concentration and cIMT in the total population although we observed directionally differing effects in men and women. Stratified results suggested associations in individuals with different cardiometabolic risk factor profiles, which require replication.

The impact of common polymorphisms in CETP and ABCA1 genes with the risk of coronary artery disease in Saudi Arabians

Background

Coronary artery disease (CAD) is a leading cause of morbidity and mortality worldwide. Many genetic and environmental risk factors including atherogenic dyslipidemia contribute towards the development of CAD. Functionally relevant mutations in the dyslipidemia-related genes and enzymes involved in the reverse cholesterol transport system are associated with CAD and contribute to increased susceptibility of myocardial infarction (MI).

Method

Blood samples from 990 angiographically confirmed Saudi CAD patients with at least one event of myocardial infarction were collected between 2012 and 2014. A total of 618 Saudi controls with no history or family history of CAD participated in the study. Four polymorphisms, rs2230806, rs2066715 (ABCA1), rs5882, and rs708272 (CETP), were genotyped using TaqMan Assay.

Results

CETP rs5882 (OR = 1.45, P < 0.005) and ABCA1 rs2230806 (OR = 1.42, P = 0.017) polymorphisms were associated with increased risk of CAD. However, rs708272 polymorphism showed protective effect (B1 vs. B2: OR = 0.80, P = 0.003 and B2B2 vs. B1B1: OR = 0.68, P = 0.012) while the ABCA1 variant rs2066715 was not associated.

Conclusion

This study is the first to report the association of these polymorphisms with CAD in the population of the Eastern Province of Saudi Arabia. The rs5882 polymorphism (CETP) showed a significant association and therefore could be a promising marker for CAD risk estimation while the rs708272 polymorphism had a protective effect from CAD.