Apolipoprotein A5 3'-UTR variants and cardiometabolic traits in Koreans: results from the Korean genome and epidemiology study and the Korea National Health and Nutrition Examination Survey

Genetic Determinants of Visit-to-Visit Lipid Variability: Genome-Wide Association Study in Statin-Naïve Korean Population

Background and Aim

There is a growing evidence that fluctuation in lipid profiles is important in cardiovascular outcomes. We aimed to identify single nucleotide polymorphism (SNP) variants associated with low-density lipoprotein-cholesterol (LDL-C) and high-density lipoprotein-cholesterol (HDL-C) variability in statin-naïve Korean subjects and evaluate their associations with coronary atherosclerosis.

Methods

In statin-naïve subjects from Gene-Environment of Interaction and phenotype cohort, we performed genome-wide association studies of lipid variability; the discovery (first) and replication (second) sets included 4,287 and 1,086 subjects, respectively. Coronary artery calcium (CAC) score and degree of coronary artery stenosis were used as outcome measures. Cholesterol variability was determined by standard deviation and average successive variability, and significant coronary atherosclerosis was defined as CAC score ≥400 or coronary stenosis ≥70%.

Results

Mean HDL-C and LDL-C level were 54 ± 12 and 123 ± 30 mg/dL in the first set and 53 ± 12 and 126 ± 29 mg/dL in the second set. APOA5 rs662799 and APOA5 rs2266788 were associated with LDL-C variability and PXDNL rs80056520, ALDH2 rs671, HECTD4 rs2074356, and CETP rs2303790 were SNPs associated for HDL-C variability. APOA5 rs662799 passed Bonferroni correction with p-value of 1.789 × 10⁻⁹. Among the SNPs associated with cholesterol variability, rs80056520 and rs2266788 variants were associated with CACS ≥400 and coronary stenosis ≥70% and rs662799 variant was associated with coronary stenosis ≥70%.

Conclusion

Two SNPs associated with LDL-C variability (APOA5 rs662799 and rs2266788) and one SNP associated with HDL-C variability (PXDNL rs80056520) were significantly associated with advanced coronary artery stenosis. Combining GWAS results with imaging parameters, our study may provide a deeper understanding of underlying pathogenic basis of the link between lipid variability and coronary atherosclerosis.

The Rise of ST-Elevation Myocardial Infarction in Women of Northeast China

The women of China's Liaoning province display some morbidities in ways that defy medical explanation. Women have higher rates of hypertension, hypercholesterolemia, and metabolic syndrome than men, an anomaly for all three conditions. Most of these patients also suffer from Type 2 Diabetes Mellitus (T2DM) while there was a negative association between being female and T2DM for the rest of China. Each of these conditions can exist independently, but the increase in both their rates and congruence is a recent phenomenon. Stranger still is that Liaoning women are now presenting in hospital emergency departments with ST-Elevation Myocardial Infarction (STEMI), while diabetics predominantly suffer more benign Non-STEMI (NSTEMI) events. Confounding factors in any attempt to study this phenomenon include trace metals like manganese that have been shown to reduce systolic blood pressure in Asian men and raise it in Asian women. Some of the phenomenon may also be associated with the gene for Apolipoprotein 5, but its recent nature suggests other factors besides lipid profiles. Trace metals in the air, water, and diet of Liaoning province, or any urban environment, could play a role.

Association of rs662799 variant and APOA5 gene haplotypes with metabolic syndrome and its components: a meta-analysis in North Africa

Apolipoprotein A5 (APOA5) has been linked to metabolic syndrome (MetS) in several populations. In North Africa, only the Tunisian and Moroccan populations were investigated. Our aim is to assess the association between APOA5 gene variant (rs662799) and haplotypes with MetS in Tunisian population and to perform a meta-analysis in North Africa. A total of 594 Tunisian participants were genotyped for polymorphism rs662799 using KASPar technology. Two polymorphisms rs3135506 and rs651821 in APOA5 gene genotyped in our previous study, were used in addition to rs662799 to assess the haplotype association with MetS. The genotype of 875 participants was used for the meta-analysis. Statistical analyses were performed with R software.

The rs662799 increases the risk of MetS under the dominant (P=0.018) and the additive models (P=0.028) in the Tunisian population. After stratification of the cohort following the sex and the geographic origin, a positive association of rs662799 with MetS was found for participant from the Northern region and for the women group. Only the haplotype AGT showed a significant association with MetS by decreasing the risk of the disease.

The meta-analysis reported a significant association of rs662799 and rs3135506 with MetS.

Our results showed a significant association between the APOA5 gene variants rs662799 and haplotypes with MetS and its traits in Tunisia. An impact of the sex and the geographic origin on the genotype distribution was highlighted. Our funding emphasizes the role of APOA5 in the development of MetS in North Africa.

Alcohol, Carbohydrate, and Calcium Intakes and Smoking Interactions with APOA5 rs662799 and rs2266788 were Associated with Elevated Plasma Triglyceride Concentrations in a Cross-Sectional Study of Korean Adults

BACKGROUND

Plasma triglyceride (TG) concentrations are markedly higher among Asians, which may be associated with the interaction of genetics and lifestyle factors.

OBJECTIVE

The purpose of this study was to investigate the genetic variants that have a strong association with plasma TG concentrations from genome-wide association study and to identify lifestyle interactions with the genetic variants that are associated with dyslipidemia in a cohort of Korean adults.

DESIGN

Korean genome and epidemiology study utilized a cross-sectional design of Koreans to determine genetic variants and lifestyle factors, including nutrient intakes, in a retrospective hospital-based city cohort conducted by the Korean Center for Disease and Control during 2004-2013.

PARTICIPANTS

Korean adults aged 40 to 77 years were participants (n=28,445).

MAIN OUTCOME MEASURES

The genetic variants that influence plasma TG concentrations were selected by genome-wide association study using an allele genetic model after adjusting for age, sex, area of residence, and body mass index. Lipid profiles and nutrient intakes from food frequency questionnaires were measured. The interactions between the single nucleotide polymorphisms and lifestyle factors were determined to influence plasma TG levels.

RESULTS

Carrying the minor alleles of APOA5 rs662799 and rs2266788 had an association with higher plasma TG concentrations by 1.86- and 1.51-fold, respectively, compared with those with the major allele (P=8.89E-150 and P=4.75E-68, respectively). Sex had an interaction with these single nucleotide polymorphisms, with males having higher plasma TG concentrations. The single nucleotide polymorphisms had significant interactions with carbohydrate, fat, and calcium intakes; alcohol consumption; and smoking status that were associated with plasma TG concentrations. Carriers with the minor allele of each single nucleotide polymorphisms had higher plasma TG concentrations when consuming-low fat (<15%) and high carbohydrate (≥72%) diets than those with major alleles. Carriers of the minor alleles with low calcium intakes (<500 mg/day) experienced elevated plasma TG concentrations compared with carriers of the major alleles. Smokers and alcohol drinkers with either of the minor alleles of APOA5, rs662799 or rs2266788, had higher plasma TG concentrations than those with its major allele.

CONCLUSIONS

These results indicated that carrying the minor alleles of APOA5 rs662799 and rs2266788, especially for men, was associated with elevated TG concentrations and suggested that Korean carriers of the minor alleles could be at increased risk of hypertriglyceridemia. Further research is needed to investigate the efficacy of modulating lifestyle factors to prevent dyslipidemia in people carrying the minor alleles of APOA5 rs662799 and rs2266788.

Association of circulating 25-hydroxyvitamin D levels with hypertension and blood pressure values in Korean adults: A Mendelian randomization study on a subset of the Korea National Health and Nutrition Survey 2011-2012 population

BACKGROUND/OBJECTIVES

Lower circulating 25-hydroxyvitamin D [25(OH)D] levels are associated with a higher risk of hypertension (HTN); however, it remains unclear whether the relationship is causal. We aimed to evaluate the causal effects of circulating 25(OH)D levels on the prevalence of HTN in the Korean population using the Mendelian randomization (MR) approach.

SUBJECTS/METHODS

Epidemiological data, serum 25(OH)D data, and genomic DNA biospecimens were obtained from 2,591 participants, a subset of the study population in the Korea National Health and Nutrition Survey 2011-2012. Five 25(OH)D-related single nucleotide polymorphisms (SNPs; DHCR7 rs12785878, CYP2R1 rs10741657, CYP2R1 rs12794714, CYP24A1 rs6013897, and GC rs2282679), identified a priori from genome-wide association studies, were used as instrument variables (IVs) for serum 25(OH)D levels. In the MR analysis, we performed IV analyses using the two-stage least squares method.

RESULTS

In the observational analysis, circulating 25(OH)D levels were found to be inversely associated with the HTN prevalence in ordinary least squares models (odds ratio: 0.97, 95% confidence interval: 0.96, 0.99) after adjusting for the potential confounders. There were differences in the circulating 25(OH)D levels across genotypes of individual SNPs. In the MR analysis, using individual SNPs as IVs, 25(OH)D levels were not associated with the HTN prevalence.

CONCLUSIONS

We found no association between genetically determined circulating 25(OH)D levels and HTN in Korean adults. Our results are listed owing to the relatively small sample size and possible weak instrument bias; therefore, further studies are needed to confirm these results.

Pharmacogenetics of statins treatment: Efficacy and safety

WHAT IS KNOWN AND OBJECTIVE

Statins are widely used worldwide in the prevention and treatment of coronary atherosclerotic heart disease and ischaemic stroke. However, in clinical application, statins have shown great individual differences in terms of the efficacy and safety, some of which are related to genetic factors. The purpose of this article was to summarize the recent advances about the correlation between gene polymorphisms and the efficacy/safety of statins.

METHODS

We searched the databases including PharmGKB and PubMed (published before June 2019) using the keywords such as 'statin', 'gene polymorphism' and 'SNP' and obtained more than 100 articles. In this review, we described the clinical studies of genetic variants associated with both the efficacy and adverse reactions of statins. We also clarified the importance of taking pharmacogenetic variation into account to improve the clinical application of statins.

RESULTS AND DISCUSSION

The available data were collected and analysed to present the polymorphisms of candidate genes encoding the most promising proteins including SLCO1B1 (encoding uptake transporters); ABCB1, ABCC2, ABCG2 (encoding effluent transporter); APOE, APOA5 (encoding apolipoprotein); genes encoding cytochrome P450 enzyme system; KIF6, HMGCR, LDLR, LPA, PCSK9, COQ2, CETP, etc These genes were proved to be related to the pharmacodynamics and pharmacokinetics of statins, thus affecting the efficacy and safety.

WHAT IS NEW AND CONCLUSION

In this paper, the correlation between gene polymorphisms and the efficacy/safety of statins was summarized. The authors reached a consensus that the variants of the genes encoding uptake and effluent transporters have the most effect on the efficacy/safety of statins. It pointed out that it is desirable to do genetic testing of these transporter genes to reduce the incidence of myopathy or to achieve better outcomes before patients use statins, especially in the regions with high frequency of risk allele.

Influence of APOA5 Locus on the Treatment Efficacy of Three Statins: Evidence From a Randomized Pilot Study in Chinese Subjects

Pharmacogenetics or pharmacogenomics approaches are important for addressing the individual variabilities of drug efficacy especially in the era of precision medicine. One particular interesting gene to investigate is APOA5, which has been repeatedly linked with the inter-individual variations of serum triglycerides. Here, we explored APOA5-statin interactions in 195 Chinese subjects randomized to rosuvastatin (5–10 mg/day), atorvastatin (10–20 mg/day), or simvastatin (40 mg/day) for 12 weeks by performing a targeted genotyping analysis of the APOA5 promoter SNP rs662799 (-1131T > C). There were no significant differences between the treatment arms for any of the statin-induced changes in clinical biomarkers. Reductions in LDL cholesterol were influenced by the APOA5 genotype in all three treatment groups. By contrast, changes in HDL cholesterol, and triglycerides were only affected by the APOA5 genotype in the atorvastatin and simvastatin groups and not in the rosuvastatin group. Our results suggest that future studies may need to consider stratifying subjects not only by genetic background but also by prescribed statin type.