ABCA1 gene was initially implicated in Tangier disease and familial hypoalphalipoproteinemia and has been shown to be associated with coronary artery disease and atherosclerosis as well.
Several studies have investigated the influence of ABCA1 variation on lipid metabolism and coronary heart disease, but they have resulted in controversial and inconsistent results.
These results suggest that defective ABCA1 function in cholesterol-loaded macrophages is one potential contributor to the impaired RCT process and the increased coronary heart disease risk in subjects with familial low HDL.
Subgroup analysis by ethnicity suggested that there were significant associations between the ABCA1rs4149313 polymorphism and an increased risk of CHD in Asian populations, but not in Caucasian populations (all P > 0.05).
Association between the ABCA1-565C/T gene promoter polymorphism and coronary heart disease severity and cholesterol efflux in the Chinese Han population.
In subjects with coronary artery disease (CAD+), the prevalence of FABP-2 54TT genotype was higher (16.5% versus 5.2%) and that of ABCA1 219RK and KK genotypes lower (33.0% versus 51.5%) than in subjects with no CAD.
We investigated whether common ABCA1 variants, previously reported to have phenotypic effects in humans, were associated with plasma lipids and CHD in a prospective study of coronary heart disease (CHD) in healthy women.
We investigated mRNA expression levels using reverse transcription-polymerase chain reaction of genes involved in cholesterol uptake (macrophage scavenger receptor (MSR1), scavenger receptor class B member 1 (SRB1), lectin-like oxidized low-density lipoprotein (LDL) receptor 1 (LOX1), CD36, LDL receptor (LDLR)), reverse cholesterol transport (apolipoprotein E (ApoE), ATP-binding cassette sub-family A member 1 (ABCA1)) and inflammation (tumour necrosis factor-alpha (TNF-alpha), macrophage inflammatory protein-1alpha (MIP-1alpha), interleukin-6 (IL-6), tissue factor) in CD14(+) monocytes from 119 consecutively recruited patients and found that median CD36 mRNA expression levels were significantly increased in patients with CHD compared with controls (111 x 10(3) vs 96 x 10(3) copies/10(6) copies beta-actin, respectively; n = 79 and 40, respectively; P < 0.05), despite a high interindividual variability in gene expression.3.
Novel polypyrimidine variation (IVS46: del T -39...-46) in ABCA1 causes exon skipping and contributes to HDL cholesterol deficiency in a family with premature coronary disease.
The multivariate model included 512 men with coronary artery disease from the REGRESS study who were completely genotyped for eight polymorphisms selected in the univariate procedure (ie, APOA1 G(-75)A, ABCA1 C(-477)T, ABCA1G1051A, APOC3 T3206G, APOE Arg158Cys, LIPC C(-514)T, LPL Asn291Ser and LPL Ser447Stop).
In conclusion, we provide additional evidence that the R219K polymorphism in the ABCA1 gene either directly or as a result of linkage disequilibrium with additional functional variant(s), has a protective effect against CHD and is associated with lower plasma triglycerides in sub-groups of patients with hyperlipidaemia.
ABCA1R219K polymorphism is associated with CHD susceptibility, and individuals with ABCA1 have a significantly higher risk of cancer particularly in Asians.
The proinflammatory enzyme myeloperoxidase induces both oxidative modification and nitrosylation of specific residues on plasma and arterial apolipoprotein A-I to render HDL dysfunctional, which results in impaired ABCA1 macrophage transport, the activation of inflammatory pathways, and an increased risk of coronary artery disease.
Novel polypyrimidine variation (IVS46: del T -39...-46) in ABCA1 causes exon skipping and contributes to HDL cholesterol deficiency in a family with premature coronary disease.
Mutations in ABCA1, as seen in Tangier disease, result in accumulation of cellular cholesterol, reduced plasma high-density lipoprotein cholesterol, and increased risk for coronary artery disease.