A Case-Control Study of the Association of the Polymorphisms of <b><i>MTHFR</i></b> and <b><i>APOE</i></b> with Risk Factors and the Severity of Coronary Artery Disease

Abstract

Objectives: To explore the association between single-nucleotide polymorphisms (SNPs) in MTHFR and APOE and the risk of CAD and, more importantly, the severity of CAD and the profile of serum lipids, we performed a case-control study in a Chinese Han population. Methods: A total of 1,207 cases of consecutive CAD-suspected inpatients were recruited, and 406 CAD cases and 231 non-CAD controls were enrolled for the final analysis after screening for exclusion criteria. All subjects had undergone coronary angiography, and the severity of CAD was evaluated by 2 cardiologists according to the Gensini scores. The genotypes of MTHFR and APOEwere detected using real-time PCR, and then verified by Sanger sequencing. Environmental risk factors, such as age, sex, smoking, alcohol consumption, hypertension, diabetes, dyslipidemia, and BMI were collected. Statistical analyses (the χ² test, binary logistic regression analysis, and ordinal polytomous logistic regression analysis) were performed with SPSS v16.0. Results: The genotypes ofall the subjects included in the CAD and non-CAD groups in this study were successfully detected, with an agreement of 100% with Sanger sequencing. The distributions of genotypes CT and TT at MTHFR C667T were higher in CAD cases than in non-CAD controls (OR 1.99, 95% CI 1.34–2.95; OR 1.77, 95% CI 1.18–2.67; p < 0.05), whereas genotype AC at MTHFR A1298Cwas lower in CAD cases (OR 0.71, 95% CI 0.50–1.02; p < 0.05). A significant association was observed in genotypes CT and TT at MTHFR C667T and the risk of CAD (OR 1.44, 95% CI 1.27–3.67; OR 1.56, 95% CI 0.88–2.78; p < 0.05). Both genotypes and alleles of APOE were comparable in the CAD cases and non-CAD controls (p > 0.05). The genotype TT at MTHFR C667T and ε4+ at APOE were more likely to be found in the CAD subgroup with a Gensini score ≥72 (p = 0.040 and p = 0.028, respectively). Meanwhile, in the patients with genotype TT,a higher level of serum Hcy was detected, while genotype ε4+ patients possessed higher levels of serum apolipoprotein E (ApoE) and low-density lipoprotein cholesterol (LDL-C) than other genotypes. Conclusion: This study revealed that the SNP site of MTHFR C667Tis associatedwith the risk of CAD in this Chinese Han population. In addition, the genotypes of TT in MTHFR C667T and ε4+in APOE may increase the severity of CAD, and higher Hcy, LDL-C, and ApoE levels may be involved in this pathogenic process.

A minor allele of the haplotype located in the 19q13 loci is associated with a decreased risk of hyper-LDL-cholesterolemia, and a balanced diet and high protein intake can reduce the risk

“…The APOE-ε4 variant elevates serum LDL and homocysteine concentrations, thereby increasing the risk of cardiovascular diseases. Participants with CT and TT at methylenetetrahydrofolate reductase C667T are at higher risk of cardiovascular diseases than those with the CC genotype [ 27 ]. In the present study, genes in the 19q3 loci modulated serum LDL concentrations.…”

The association of apolipoprotein-E (APOE) gene polymorphisms with coronary artery disease: a systematic review and meta-analysis

“…1. The characteristics of the included studies [13][14][15][16][17][18][19][20][21][22][23][24], and the results of quality assessment based on NOS score are given in Table 1. The frequencies of APOE allele and distribution of genotypes are given in Table 2.…”

Association Between MTHFR C677T Polymorphism and Susceptibility to Autism Spectrum Disorders: A Meta-Analysis in Chinese Han Population

“…Five studies (23,26,33,44,45) deviated from HWE were excluded, leaving 12 studies on Northern Han and 13 studies on Southern Han to be pooled. A high between-study heterogeneity (I 2 = 97.6%, P < 0.01) was shown among all the studies and the pooled MAF estimated by a random-effect model was 42% (95% CI: 37-46%).…”