Quantitative assessment of the effect of ABCA1 R219K polymorphism on the risk of coronary heart disease

Role of ABCA1 in Cardiovascular Disease

Cholesterol homeostasis plays a significant role in cardiovascular disease. Previous studies have indicated that ATP-binding cassette transporter A1 (ABCA1) is one of the most important proteins that maintains cholesterol homeostasis. ABCA1 mediates nascent high-density lipoprotein biogenesis. Upon binding with apolipoprotein A-I, ABCA1 facilitates the efflux of excess intracellular cholesterol and phospholipids and controls the rate-limiting step of reverse cholesterol transport. In addition, ABCA1 interacts with the apolipoprotein receptor and suppresses inflammation through a series of signaling pathways. Thus, ABCA1 may prevent cardiovascular disease by inhibiting inflammation and maintaining lipid homeostasis. Several studies have indicated that post-transcriptional modifications play a critical role in the regulation of ABCA1 transportation and plasma membrane localization, which affects its biological function. Meanwhile, carriers of the loss-of-function ABCA1 gene are often accompanied by decreased expression of ABCA1 and an increased risk of cardiovascular diseases. We summarized the ABCA1 transcription regulation mechanism, mutations, post-translational modifications, and their roles in the development of dyslipidemia, atherosclerosis, ischemia/reperfusion, myocardial infarction, and coronary heart disease.

Association between the ABCA1 (R219K) polymorphism and lipid profiles: a meta-analysis

Conflicting evidence was found about the relationship between lipid profiles and R219K polymorphism in adenosine triphosphate-binding cassette exporter A1 (ABCA1) gene. In this study, four meta-analyses were conducted to assess the effect of R219K on lipid levels, including high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol, total cholesterol, and triglycerides (TG). A total of 125 samples of 87 studies (about 60,262 subjects) were included. The effect of each study was expressed using the standard mean difference (SMD) and 95% confidence interval (95% CI) and pooled by meta-analysis in the random-effects model. Subgroup and meta-regression analyses were conducted to explore potential heterogeneity sources. The overall pooled effect showed the following results. (1) The R219K was significantly associated with HDLC level (SMD = - 0.25 mmol/L, 95%CI - 0.32 to - 0.18, z = - 6.96, P < 0.01, recessive genetic model). People with different genotypes had significantly different HDLC levels under the recessive, codominant and dominant genetic models (all Ps < 0.01). (2) A weak and indeterminate relationship between R219K and TG level was observed (SMD = 0.18 mmol/L, 95%CI 0.06-0.30, z = 3.01, P < 0.01, recessive genetic model). These findings suggested that R219K was associated with HDLC and TG levels, which might implicate a promising clinical application for lipid-related disorders, though the influences of race, health status, BMI, and other heterogeneity sources should be considered when interpreting current findings. The protocol was registered at PROSPERO (registration number: CRD42021231178).

Weighted gene co-expression network analysis to identify key modules and hub genes related to hyperlipidaemia

BACKGROUND

The purpose of this study was to explore the potential molecular targets of hyperlipidaemia and the related molecular mechanisms.

METHODS

The microarray dataset of GSE66676 obtained from patients with hyperlipidaemia was downloaded. Weighted gene co-expression network (WGCNA) analysis was used to analyse the gene expression profile, and the royal blue module was considered to have the highest correlation. Gene Ontology (GO) functional and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were implemented for the identification of genes in the royal blue module using the Database for Annotation, Visualization and Integrated Discovery (DAVID) online tool (version 6.8; http://david.abcc.ncifcrf.gov ). A protein-protein interaction (PPI) network was established by using the online STRING tool. Then, several hub genes were identified by the MCODE and cytoHubba plug-ins in Cytoscape software.

RESULTS

The significant module (royal blue) identified was associated with TC, TG and non-HDL-C. GO and KEGG enrichment analyses revealed that the genes in the royal blue module were associated with carbon metabolism, steroid biosynthesis, fatty acid metabolism and biosynthesis pathways of unsaturated fatty acids. SQLE (degree = 17) was revealed as a key molecule associated with hypercholesterolaemia (HCH), and SCD was revealed as a key molecule associated with hypertriglyceridaemia (HTG). RT-qPCR analysis also confirmed the above results based on our HCH/HTG samples.

CONCLUSIONS

SQLE and SCD are related to hyperlipidaemia, and SQLE/SCD may be new targets for cholesterol-lowering or triglyceride-lowering therapy, respectively.

Novel associations of SNPs MYLIP rs3757354 and ABCA1 2230806 gene with early-onset-preeclampsia: A case-control candidate genetic study

OBJECTIVE

To investigate the association between MYLIP rs3757354 and ABCA1 2230806 single nucleotide polymorphisms in women with preeclampsia in China.

STUDY DESIGN

The case-control study involved 205 patients with preeclampsia and 145 controls. All women with preeclampsia were divided into two groups: 78 patients with early-onset preeclampsia and 127 with late-onset preeclampsia.

MAIN OUTCOME MEASURE

MYLIP rs3757354 and ABCA1 rs2230806 SNPs were analyzed through multiplex PCR for targeted next-generation sequencing technology. A secondary outcome was lipid profile changes and liver function in women with PE.

RESULTS

Maternal age (OR: 1.073, 95% CI = 1.006-1.145), BMI (OR: 1.118, 95% CI = 1.040-1.201), TG/HDL-C (OR: 1.536, 95% CI = 1.080-2.183), and TT genotype of SNP rs3757354 (OR: 3.238, 95% CI = 1.313-7.990) were associated with EOPE risk. Our study found that patients with TT genotype of ABCA1 rs2230806 had more severe hepatic dysfunction and higher HDL levels in the EOPE group compared with CC/CT genotype. There was no association between rs2230806 and the risk of PE.

CONCLUSION

The polymorphisms of rs3757354 are associated with the risk of EOPE in Chinese pregnant women. The TT genotype in ABCA1 rs2230806 is a strong predictive risk for elevated aminotransferase levels in pregnant women with EOPE.

Association between SLC44A4-NOTCH4 SNPs and serum lipid levels in the Chinese Han and Maonan ethnic groups

BACKGROUND

The current research was to assess the relationship of the solute carrier family 44 member 4 (SLC44A4) rs577272, notch receptor 4 (NOTCH4) rs3134931 SNPs and serum lipid levels in the Han and Maonan ethnic groups.

METHODS

The genetic makeup of the SLC44A4 rs577272 and NOTCH4 rs3134931 SNPs in 2467 unrelated subjects (Han, 1254; Maonan,1213) was obtained by using polymerase chain reaction and restriction fragment length polymorphism technique, combined with gel electrophoresis, and confirmed by direct sequencing.

RESULTS

The genotype frequencies of SLC44A4 rs577272 and NOTCH4 rs3134931 SNPs were different between Han and Maonan populations (P < 0.05); respectively. The SLC44A4 rs577272 SNP was associated with total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) levels in Maonan group. The NOTCH4 rs3134931 SNP was associated with triglyceride (TG) in Han; and TG and low-density lipoprotein cholesterol (LDL-C) levels in Maonan groups (P < 0.025-0.001). Stratified analysis according to gender showed that the SLC44A4 rs577272 SNP was associated with TC and HDL-C in Han and Maonan females; TC in Maonan males, meanwhile, the NOTCH4 rs3134931 SNP was associated with TG and HDL-C in Han males; TG in Han females; TG and LDL-C in Maonan males; and TG, HDL-C and LDL-C in Maonan females. Linkage disequilibrium analysis showed that the most common haplotype was rs577272G-rs3134931A (> 50%) in both Han and Maonan groups. The haplotype of rs577272G-rs3134931A was associated with TG and HDL-C in Han; and TC, TG and HDL-C in Maonan ethnic groups.

CONCLUSIONS

These results suggest that the relationship among SLC44A4 rs577272, NOTCH4 rs3134931 SNPs and serum lipid parameters may vary depending on the gender and/or ethnicity/race in some populations. Haplotypes could explain more changes in serum lipid parameters than any single SNP alone particularly for TC, TG and HDL-C.

Association between the XKR6 rs7819412 SNP and serum lipid levels and the risk of coronary artery disease and ischemic stroke

Background

The present study aimed to expound the association between the XK related 6 gene (XKR6) rs7819412 single nucleotide polymorphism (SNP) and serum lipid profiles and the risk of coronary artery disease (CAD) and ischemic stroke.

Methods

The genetic makeup of the XKR6 rs7819412 SNP in 1783 unrelated participants (controls, 643; CAD, 588 and ischemic stroke, 552) of Han Chinese was obtained by the Snapshot technology.

Results

The genotypic frequencies of the SNP were disparate between CAD (GG, 81.0%; GA/AA, 19.0%) or ischemic stroke (GG, 81.2%; GA/AA, 18.8%) patients and healthy controls (GG, 85.7%, GA/AA, 14.3%; P < 0.05 vs. CAD or ischemic stroke; respectively). The A allele frequency was also diverse between CAD (10.1%) or ischemic stroke (10.0%) and control groups (7.5%; P < 0.05 vs. CAD or ischemic stroke; respectively). The GA/AA genotypes and A allele were associated with high risk of CAD and ischemic stroke (CAD: P = 0.026 for GA/AA vs. GG, P = 0.024 for A vs. G; Ischemic stroke: P = 0.029 for GA/AA vs. GG, P = 0.036 for A vs. G). The GA/AA genotypes were also associated with increased serum triglyceride (TG) concentration in CAD and total cholesterol (TC) concentration in ischemic stroke patients.

Conclusions

These data revealed that the XKR6 rs7819412 A allele was related to increased serum TG levels in CAD, TC levels in ischemic stroke patients and high risk of CAD and ischemic stroke.

The C-565T Polymorphism (rs2422493) of the ATP-binding Cassette Transporter A1 Gene Contributes to the Development and Severity of Coronary Artery Disease in an Iranian Population

Objectives

ATP-binding cassette transporter A1 (ABCA1) plays a pivotal role in reverse cholesterol transport from peripheral tissues back to the liver. Abnormalities in ABCA1 function may lead to dyslipidemia and coronary artery disease (CAD). We investigated the role of C-565T (rs2422493) promoter polymorphism of ABCA1 gene in the development and severity of CAD in an Iranian subpopulation.

Methods

Our study population consisted of 110 angiographically-confirmed CAD patients and 110 matched controls. The severity of CAD was expressed based on the number of stenotic vessels. Genotyping of C-565T promoter polymorphism was performed using the polymerase chain reaction followed by restriction fragments length polymorphism analysis methods. Lipid profile was determined by routine colorimetric methods.

Results

The distribution of ABCA1 C-565T genotypes (p = 0.035) and alleles (p = 0.017) was significantly different between the CAD and control groups. In univariate analysis (with genotype CC as reference), the TT genotype was significantly associated with an increased risk of CAD (odds ratio = 3.83; 95% confidence interval: 1.29-11.30, p = 0.014), but the CT genotype was not (p = 0.321). A multiple binary logistic regression analysis revealed that smoking, hypertension, triglyceride, cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and ABCA1 C-565T dominant genotype were significant and independent risk factors for CAD development (p < 0.050). The ABCA1 C-565T polymorphism affected the severity of CAD in TT homozygote state (p = 0.028). However, no significant correlation was seen between this common polymorphism and lipid profile in the study population (p > 0.050). Conclusions: Our study indicated that ABCA1 C-565T polymorphism is a significant risk factor for development and severity of CAD in our population.

Association Study of the ATP - Binding Cassette Transporter A1 (ABCA1) Rs2230806 Genetic Variation with Lipid Profile and Coronary Artery Disease Risk in an Iranian Population

BACKGROUND:

ATP - binding cassette transporter A1 (ABCA1) plays essential roles in the biogenesis of high -density lipoprotein - cholesterol. Variations in the ABCA1 gene may influence the risk of coronary artery disease (CAD).

AIM:

Present study aimed to investigate the association of rs2230806 (R219K) polymorphism of ABCA1 gene with the development and severity of CAD in an Iranian population.

MATERIALS AND METHODS:

Our study population consisted of 100 patients with angiographically confirmed CAD and 100 controls. The genotyping of R219K mutation of ABCA1 gene was determined by PCR - RFLP method. Lipid profile was determined using routine colourimetric assays. Statistical analysis was done by SPSS - 16.

RESULTS:

The genotypic (P = 0.024) and allelic (P = 0.001) distribution of the ABCA1 R219K polymorphism were significantly different between the two groups. In a univariate analysis (with genotype RR as the reference), the RK genotype (OR = 0.46, 95%CI = 0.25-0.86, P = 0.020) and KK genotype (OR = 0.27, 95%CI = 0.11 – 0.66, P = 0.005) was significantly associated with a decreased risk of CAD. A multiple logistic regression analysis revealed that smoking (0.008), diabetes (P = 0.023), triglyceride (P = 0.001), HDL - cholesterol (P = 0.002) and ABCA1 KK genotype (P = 0.009) were significantly and independently associated with the risk of CAD. The association between different genotypes of R219K polymorphism with lipid profile was not significant in both groups (P > 0.05). The R219K polymorphism was significantly associated with severity of CAD (P < 0.05).

CONCLUSION:

The carriage of K allele of ABCA1 R219K polymorphism has a protective effect on CAD risk and correlates with a decreased severity of CAD. This protective effect seems to be mediated independently of plasma lipid levels.

Evaluation of Adenosine Triphosphate-Binding Cassette Transporter A1 (ABCA1) R219K and C-Reactive Protein Gene (CRP) +1059G/C Gene Polymorphisms in Susceptibility to Coronary Heart Disease

Background

This meta-analysis investigated the correlation of ABCA1 R219K and CRP +1059G/C gene polymorphisms with susceptibility to coronary heart disease (CHD).

Material/Methods

We searched PubMed, Springer link, Wiley, EBSCO, Ovid, Wanfang database, VIP database, and China National Knowledge Infrastructure (CNKI) databases to retrieve published studies by keyword. Searches were filtered using our stringent inclusion and exclusion criteria. Resultant high-quality data collected from the final selected studies were analyzed using Comprehensive Meta-analysis 2.0 software. Eleven case-control studies involving 3053 CHD patients and 3403 healthy controls met our inclusion criteria. Seven studies were conducted in Asian populations, 3 studies were done in Caucasian populations, and 1 was in an African population.

Results

Our major finding was that ABCA1 R219K polymorphism increased susceptibility to CHD in allele model (OR=0.729, 95% CI=0.559~0.949, P=0.019) and dominant model (OR=0.698, 95% CI=0.507~0.961, P=0.027). By contrast, we were unable to find any significant association between the CRP +1059G/C polymorphism and susceptibility to CHD (allele model: OR=1.170, 95% CI=0.782~1.751, P=0.444; dominant model: OR=1.175, 95% CI=0.768~1.797, P=0.457).

Conclusions

This meta-analysis provides convincing evidence that polymorphism of ABCA1 R219K is associated with susceptibility to CHD while the CRP +1059G/C polymorphism appears to have no correlation with susceptibility to CHD.

A Comprehensive In Silico Analysis of the Functional and Structural Impact of Nonsynonymous SNPs in the ABCA1 Transporter Gene

Disease phenotypes and defects in function can be traced to nonsynonymous single nucleotide polymorphisms (nsSNPs), which are important indicators of action sites and effective potential therapeutic approaches. Identification of deleterious nsSNPs is crucial to characterize the genetic basis of diseases, assess individual susceptibility to disease, determinate molecular and therapeutic targets, and predict clinical phenotypes. In this study using PolyPhen2 and MutPred in silico algorithms, we analyzed the genetic variations that can alter the expression and function of the ABCA1 gene that causes the allelic disorders familial hypoalphalipoproteinemia and Tangier disease. Predictions were validated with published results from in vitro, in vivo, and human studies. Out of a total of 233 nsSNPs, 80 (34.33%) were found deleterious by both methods. Among these 80 deleterious nsSNPs found, 29 (12.44%) rare variants resulted highly deleterious with a probability >0.8. We have observed that mostly variants with verified functional effect in experimental studies are correctly predicted as damage variants by MutPred and PolyPhen2 tools. Still, the controversial results of experimental approaches correspond to nsSNPs predicted as neutral by both methods, or contradictory predictions are obtained for them. A total of seventeen nsSNPs were predicted as deleterious by PolyPhen2, which resulted neutral by MutPred. Otherwise, forty two nsSNPs were predicted as deleterious by MutPred, which resulted neutral by PolyPhen2.

Influence of ATP-binding cassette transporter 1 R219K and M883I polymorphisms on development of atherosclerosis: a meta-analysis of 58 studies

Background

Numerous epidemiological studies have evaluated the associations between ATP-binding cassette transporter 1 (ABCA1) R219K (rs2230806) and M883I (rs4149313) polymorphisms and atherosclerosis (AS), but results remain controversial. The purpose of the present study is to investigate whether these two polymorphisms facilitate the susceptibility to AS using a meta-analysis.

Methods

PubMed, Embase, Web of Science, Medline, Cochrane database, Clinicaltrials.gov, Current Controlled Trials, Chinese Clinical Trial Registry, CBMdisc, CNKI, Google Scholar and Baidu Library were searched to get the genetic association studies. All statistical analyses were done with Stata 11.0.

Results

Forty-seven articles involving 58 studies were included in the final meta-analysis. For the ABCA1 R219K polymorphism, 42 studies involving 12,551 AS cases and 19,548 controls were combined showing significant association between this variant and AS risk (for K allele vs. R allele: OR = 0.77, 95% CI = 0.71–0.84, P<0.01; for K/K vs. R/R: OR = 0.60, 95% CI = 0.51–0.71, P<0.01; for K/K vs. R/K+R/R: OR = 0.69, 95% CI = 0.60–0.80, P<0.01; for K/K+R/K vs. R/R: OR = 0.74, 95% CI = 0.66–0.83, P<0.01). For the ABCA1 M883I polymorphism, 16 studies involving 4,224 AS cases and 3,462 controls were combined. There was also significant association between the variant and AS risk (for I allele vs. M allele: OR = 0.85, 95% CI = 0.77–0.95, P<0.01).

Conclusions

The present meta-analysis suggested that the ABCA1 R219K and M883I polymorphisms were associated with the susceptibility to AS. However, due to the high heterogeneity in the meta-analysis, the results should be interpreted with caution.

ATP-binding cassette transporter A1 R219K polymorphism and ischemic stroke risk in the Chinese population: a meta-analysis

Recently, many studies have been focused on the association between the ATP-binding cassette transporter A1 (ABCA1) gene R219K polymorphism and ischemic stroke (IS). However, the study results have been inconsistent, especially in the Chinese population. Therefore, we performed a meta-analysis to better clarify the association between the ABCA1 gene and IS. All of the relevant studies used in our meta-analysis were identified using PubMed, OVID, Cochrane Library, Chinese Wan Fang database, Chinese VIP database, China National Knowledge Infrastructure (CNKI), and China Biological Medicine Database (CBM) up to May 2013. Statistical analysis was conducted with STATA software version 11.0. Odds ratios with 95% confidence intervals were applied to evaluate the strength of the association between ABCA1 gene R219K polymorphism and IS. Heterogeneity was evaluated using the Q-test and I(2) statistic. The funnel plots, Begg's and Egger's regression tests were used to assess the publication bias. Our meta-analysis showed the dominant genetic model (OR=0.92, 95% CI: 0.88-0.96), the recessive genetic model (OR=0.73, 95% CI: 0.51-1.05), the homozygote genetic model (OR=0.64, 95% CI: 0.44-0.94), the heterozygote genetic model (OR=0.81, 95% CI: 0.69-0.95), and the allelic genetic model (OR=0.83, 95% CI: 0.69-0.99). For R219K in IS, there were significant associations with these genetic models, but not with the recessive genetic model. Our meta-analysis indicated that the ABCA1 gene R219K polymorphism might be associated with IS and the K allele might be a protective factor in the Chinese population.

The ABCA1 gene R230C variant is associated with decreased risk of premature coronary artery disease: the genetics of atherosclerotic disease (GEA) study

BACKGROUND

ABCA1 genetic variation is known to play a role in HDL-C levels and various studies have also implicated ABCA1 variation in cardiovascular risk. The functional ABCA1/R230C variant is frequent in the Mexican population and has been consistently associated with low HDL-C concentrations. Although it has been associated with other cardiovascular risk factors such as obesity and type 2 diabetes mellitus, it is not known whether it is associated with coronary artery disease (CAD).

AIM

The purpose of the study was to analyze whether the ABCA1/R230C variant is associated with premature CAD in a case-control association study (GEA or Genetics of Atherosclerotic Disease), and to explore whether BMI modulates the effect of the C230 allele on other metabolic traits using a population-based design.

RESULTS

The C230 allele was significantly associated with both lower HDL-C levels and a lower risk of premature CAD as compared to controls (OR = 0.566; P(add) = 1.499×10(-5)). In addition, BMI modulated the effect of R230C on body fat distribution, as the correlation between BMI and visceral to subcutaneous adipose tissue (a metric of the propensity to store fat viscerally as compared to subcutaneously) was negative in RR homozygous individuals, but positive in premenopausal women bearing the C230 allele, with a statistically significant interaction (P = 0.005). BMI-R230C interaction was also significant for triglyceride levels in women regardless of their menopausal status (P = 0.036).

CONCLUSION

This is the first study assessing the effect of the R230C/ABCA1 variant in remature CAD. C230 was associated with both decreased HDL-C levels and a lower risk of premature CAD, and gender-specific BMI-R230C interactions were observed for different metabolic traits. These interactions may help explain inconsistencies in associations, and underscore the need to further analyze interactions of this functional and frequent variant with diet, exercise and other environmental factors.