Genetic polymorphism of apolipoprotein A5 gene and susceptibility to type 2 diabetes mellitus: a meta-analysis of 15,137 subjects

The Apo gene's genetic variants: hidden role in Asian vascular risk

Vascular risk factors, including diabetes, hypertension, hyperlipidemia, and obesity, pose significant health threats with implications extending to neuropsychiatric disorders such as stroke and Alzheimer's disease. The Asian population, in particular, appears to be disproportionately affected due to unique genetic predispositions, as well as epigenetic factors such as dietary patterns and lifestyle habits. Existing management strategies often fall short of addressing these specific needs, leading to greater challenges in prevention and treatment. This review highlights a significant gap in our understanding of the impact of genetic screening in the early detection and tailored treatment of vascular risk factors among the Asian population. Apolipoprotein, a key player in cholesterol metabolism, is primarily associated with dyslipidemia, yet emerging evidence suggests its involvement in conditions such as diabetes, hypertension, and obesity. While genetic variants of vascular risk are ethnic-dependent, current evidence indicates that epigenetics also exhibits ethnic specificity. Understanding the interplay between Apolipoprotein and genetics, particularly within diverse ethnic backgrounds, has the potential to refine risk stratification and enhance precision in management. For Caucasian carrying the APOA5 rs662799 C variant, pharmacological interventions are recommended, as dietary interventions may not be sufficient. In contrast, for Asian populations with the same genetic variant, dietary modifications are initially advised. Should dyslipidemia persist, the consideration of pharmaceutical agents such as statins is recommended.

Nomogram developed with APOA5 genetic variant rs662799 and clinical characteristics predicting risk of essential hypertension in a Chinese population

Background

The apolipoprotein A5 (APOA5) gene has been identified as a key regulatory factor in triglyceride (TG) metabolism and plasma lipid levels. Genetic polymorphisms of APOA5 have been linked to an elevated risk of atherosclerosis, metabolic syndrome, stroke, and coronary artery disease. The rs662799 variant is a single nucleotide polymorphism (SNP) that occurs at a specific position within the APOA5 gene. However, the association between rs662799 polymorphism and essential hypertension (EHT) remains unclear. The study aimed to comprehensively examine the potential correlation between the rs662799 polymorphism and the susceptibility to EHT in a Chinese population using a systematic analysis.

Methods

In a case study conducted at the First Affiliated Hospital of Xinjiang Medical University between Jan 2019 and Dec 2021, we examined a total of 700 cases of EHT along with 700 corresponding controls. The serum concentrations of various lipid parameters were measured by enzymatic method, while the genotyping of the SNP was performed using the improved multiplex ligation detection reaction (iMLDR) method. The independent risk factors of EHT were identified from multivariable logistic regression analysis. The nomogram prediction model that incorporated the APOA5 genetic variations and clinical variables was constructed. In addition, receiver operating characteristic (ROC) curve and Hosmer-Lemeshow test were conducted to determine the performance of the nomogram model. The optimal threshold was calculated based on Youden index.

Results

Our study revealed a higher prevalence of the G allele of the rs662799 variant in individuals diagnosed with EHT compared to the control group. Logistic regression analysis indicated that with the adjustment of other confounders, the observed difference between the two groups remained statistically significant [odds ratio (OR) =1.519; 95% confidence interval (CI): 1.203-1.917; P<0.001]. Based on 8 independent risk factors including APOA5 rs662799 G allele, age, body mass index (BMI), smoking, diabetes, education, low-density lipoprotein cholesterol (LDL-C), and TG, we constructed a novel risk evaluation nomogram of EHT. The area under the ROC curve of the nomogram was 0.722 (95% CI: 0.693-0.752; P<0.001) and 0.747 (95% CI: 0.690-0.804; P<0.001) for the training and validation set, respectively. Furthermore, the Hosmer-Lemeshow test indicated excellent calibration performance, yielding P values of 0.969 for the training set and 0.761 for the validation set.

Conclusions

In our study, the rs662799 variant of the APOA5 gene was significantly associated with susceptibility to EHT. A nomogram for the early prediction of EHT in in the Chinese population was successfully constructed and validated. The nomogram can provide a visual assessment of the risk of EHT for clinical consultation.

Genetic association analysis of rs662799 ( − 1131A > G) polymorphism of APOA5 gene with morphometric and physio-metric traits using multiplex PCR

Background

The apolipoprotein A5 (APOA5) gene, significantly expressed in liver, has been involved in regulation of triglyceride metabolism, plasma lipid levels, serum adipokine levels and cardiovascular traits. A single-nucleotide polymorphism rs662799 ( − 1131A > G), 2 Kb upstream in the promoter region of this gene, causes decrease in the concentration of the product coded by this gene; hence, it may be responsible for impairments in normal function of the gene, ultimately leading to disease condition. Keeping in view the importance of APOA5 gene, the aim of the present study was to examine the association of genetic variant rs662799 of APOA5 gene with two quantitative traits simultaneously, viz. body mass index and blood pressure.

Results

The study involved a population of 246 subjects from North Indian region. Measurements of morphometric and physio-metric parameters were recorded using standard measures. Genotyping of APOA5 gene polymorphism (rs662799) using Tetra-primer amplification refractory mutation system PCR was performed. Statistical analyses were carried out using MS-Excel and SigmaPlot, and significance level was setup as p < 0.05. The allelic distribution of rs662799 polymorphism in this population was 77% for major allele (A) and 23% for minor allele (G). Significant association of rs662799 with increased body mass index and blood pressure was observed, with the presence of allele G. Under recessive genetic model, rs662799 polymorphism conferred a 17.71-fold risk of elevated body mass index (OR = 17.71, p < 0.001, CI (95%) = 4.05–77.46), and for increase in blood pressure, 3.79- and 3.83-fold risk of systolic blood pressure and diastolic blood pressure (OR = 3.792, p = 0.023, CI (95%) = 1.25–11.509 and OR = 3.83, p = 0.012, CI (95%) = 1.375–10.68, respectively) was observed. Under dominant genetic model, it showed a 3.060-fold risk of increase in body mass index (OR = 3.060, p < 0.001, CI (95%) = 1.78–5.25).

Conclusions

G allele of rs662799 of APOA5 gene showed significant susceptible association with BMI and BP. This study may be helpful for clinicians and researchers to investigate the diagnostic and prognostic value of the gene in question.

Genetic Association between Different Metabolic Variants in APOA5 and PLIN1 in Type 2 Diabetes Mellitus among the Western Saudi Population: Case-Control Study

Type 2 diabetes mellitus (T2DM) is a multifactorial disease with a high global incidence. Hypertriglyceridemia is a major risk factor for both cardiovascular disease and T2DM. In this study, we determined the allele and genotype frequencies of apolipoprotein A5 (APOA5) single nucleotide polymorphism (SNP) rs662799 and perilipin 1 (PLIN1) SNPs rs894160, rs6496589, and rs1052700 and evaluated their association with T2DM risk in western Saudis. Only rs6496589 was found to be significantly associated with T2DM risk. We determined the risk allele for each SNP based on relative risk, and found that the G allele of rs662799, T allele of rs894160, G allele of r6496589, and T allele of rs1052700 correlated with T2DM risk. The effect of each SNP on T2DM risk and five of its clinical phenotypes was explored using multiple logistic regression. We found significant correlations between the C/G and G/G genotypes of rs6496589 and T2DM risk in the unadjusted model, whereas G/G was the only genotype that correlated with the risk of T2DM in the adjusted model. There was no significant correlation between rs662799, rs894160, and rs1052700 genotypes and T2DM risk. In conclusion, we have identified novel risk alleles and genotypes that contribute to genetic risk for T2DM in the western Saudi population.

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.

Multivariate analysis of genomics data to identify potential pleiotropic genes for type 2 diabetes, obesity and dyslipidemia using Meta-CCA and gene-based approach

Previous studies have demonstrated the genetic correlations between type 2 diabetes, obesity and dyslipidemia, and indicated that many genes have pleiotropic effects on them. However, these pleiotropic genes have not been well-defined. It is essential to identify pleiotropic genes using systematic approaches because systematically analyzing correlated traits is an effective way to enhance their statistical power. To identify potential pleiotropic genes for these three disorders, we performed a systematic analysis by incorporating GWAS (genome-wide associated study) datasets of six correlated traits related to type 2 diabetes, obesity and dyslipidemia using Meta-CCA (meta-analysis using canonical correlation analysis). Meta-CCA is an emerging method to systematically identify potential pleiotropic genes using GWAS summary statistics of multiple correlated traits. 2,720 genes were identified as significant genes after multiple testing (Bonferroni corrected p value < 0.05). Further, to refine the identified genes, we tested their relationship to the six correlated traits using VEGAS-2 (versatile gene-based association study-2). Only the genes significantly associated (Bonferroni corrected p value < 0.05) with more than one trait were kept. Finally, 25 genes (including two confirmed pleiotropic genes and eleven novel pleiotropic genes) were identified as potential pleiotropic genes. They were enriched in 5 pathways including the statin pathway and the PPAR (peroxisome proliferator-activated receptor) Alpha pathway. In summary, our study identified potential pleiotropic genes and pathways of type 2 diabetes, obesity and dyslipidemia, which may shed light on the common biological etiology and pathogenesis of these three disorders and provide promising insights for new therapies.

Nutrigenetic variants and cardio-metabolic risk in women with or without gestational diabetes

AIM

Gestational diabetes mellitus (GDM) is the most frequent metabolic disorder in pregnancy and it can be considered a silent risk associated to T2DM and CVD later in life. The aim of this study was to investigate the association of clinical parameters with nine single nucleotide polymorphisms (SNPs) involved with nutrients and metabolism in women with or without GDM in order to identify potential routine clinical markers for early prevention.

METHODS

Nine gene variants associated with nutrients and metabolism, namely PPARG2 rs1801282 (C > G); PPARGC1A rs8192678 (C > T); TCF7L2 rs7903146 (C > T); LDLR rs2228671 (C > T); MTHFR rs1801133 (C > T); APOA5 rs662799 (T > C); GCKR rs1260326 (C > T); FTO rs9939609 (T > A); MC4R rs17782313 (T > C) were genotyped in 104 GDM cases and 124 controls using High Resolution Melting (HRM) analysis.

RESULTS

The genetic variant rs7903146 (C > T) in TCF7L2 gene showed a strong association with GDM risk (OR: 2.56; 95% CI: [1.24-5.29]). Moreover, a significant correlation was observed between lipid parameters and polymorphisms in other genes, namely PPARG2 [p = 0,03], APOA5 [p = 0,02], MC4R [p = 0,03], LDLR [p = 0,04] and FTO [p = 0,03]. In addition, rs17782313 variant, mapped close to MC4R gene, was associated to BMI in pre-pregnancy [p = 0,02] and at the end of pregnancy [p = 0,03] in GDM group.

CONCLUSION

In our study, we found significant associations between routine clinical parameters and some gene variants connected with nutrients and metabolism in women with GDM. These results can provide useful information to develop effective tools and possible personalized intervention strategies in a timely manner.

Early Subclinical Atherosclerosis in Gestational Diabetes: The Predictive Role of Routine Biomarkers and Nutrigenetic Variants

Gestational diabetes mellitus (GDM) can be considered a silent risk for out-of-pregnancy diabetes mellitus (DM) and cardiovascular disease (CVD) later in life. We aimed to assess the predictive role of 3^rd trimester lipid profile during pregnancy for the susceptibility to markers of subclinical atherosclerosis (CVD susceptibility) at 3 years in a cohort of women with history of GDM. A secondary aim is to evaluate the usefulness of novel nutrigenetic markers, in addition to traditional parameters, for predicting early subclinical atherosclerosis in such women in order to plan adequate early prevention interventions. We assessed 28 consecutive GDM women in whom we collected socio-demographic characteristics and clinical and anthropometric parameters at the 3^rd trimester of pregnancy. In a single blood sample, from each patient, we assessed 9 single nucleotide polymorphisms (SNPs) from 9 genes related to nutrients and metabolism, which were genotyped by High Resolution Melting analysis. All women then attended a 3-year-postpartum follow-up and on that occasion performed an oral glucose tolerance test (OGTT, with 75 g oral glucose), the measurement of carotid artery intima-media thickness (cIMT), and analyses of metabolic parameters. In addition, we evaluated the physical activity level and the adherence to Mediterranean diet (MedDiet) using the International Physical Activity Questionnaire (IPAQ-short version) and PREDIMED questionnaires. We found an association between 3^rd trimester triglycerides and cIMT (p = 0.014). We also found significant associations between the APOA5 CC genotype and cIMT after adjustments for age and body mass index (p = 0.045) and between the interaction CC APOA5/CC LDLR and cIMT (p = 0.010). At the follow-up, the cohort also featured a mean BMI in the overweight range and a high mean waist circumference. We found no difference in the MedDiet adherence, physical activity, and smoking but an inverse correlation between the PREDIMED and the IPAQ scores with the IMT. In conclusion, this preliminary study provides insight into the predictive role of lipid profile during pregnancy and of some genetic variants on cIMT taken as a parameter of subclinical CVD susceptibility in GDM.

Apolipoprotein A5 fifteen years anniversary: Lessons from genetic epidemiology

Apolipoprotein A5 (APOA5) is a small protein, expressed predominantly in the liver. In plasma, it is located on triglyceride rich lipoprotein particles (chylomicrones and VLDL) and on HDL. Plasma concentration of apolipoprotein A5 is very low, suggesting rather regulatory (activation of lipoprotein lipase, …) than structural function. APOA5 is an important determinant of plasma triglyceride concentration; this effect has been confirmed both on animal models, as well as on human studies. Minor alleles of three commonly analysed variants within this gene (rs662799, rs3135506, rs2075291) are associated with higher plasma TG values and increased risk of myocardial infarction, with some important interethnic differences observed. Further roles of APOA5; determination of BMI, diabetes and last but not least nutri- and pharmaco-genetic interactions are suggested, but without the definitive conclusions.

Apolipoprotein A5 and apolipoprotein C3 single nucleotide polymorphisms are correlated with an increased risk of coronary heart disease: a case-control and meta-analysis study

Background

Triglycerides (TGs) are proatherogenic lipoproteins involving the risk of coronary heart disease (CHD), while apolipoprotein A5 (APOA5) and apolipoprotein C3 (APOC3) are main lipoproteins composing TG-rich lipoproteins. In this study, we aim to explore the correlation of CHD with APOA5 -1131 T > C and APOC3 -455 T > C single nucleotide polymorphisms (SNPs).

Methods

A sum of 210 CHD patients, hospitalized between Jan. 2013 and Mar. 2015 at China-Japan Union Hospital, Jilin University, were selected as our case group and 223 healthy individuals who had physical examination at same hospital at the same period were selected as control group. The frequency distribution of genotypes of APOA5 -1131 T > C and APOC3 -455 T > C SNPs were measured by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The Stata 12.0 software was utilized for statistical analyses.

Results

There was no significant difference on age and sex between case and control group (P > 0.05). History of smoking, drinking, hypertension and diabetes mellitus, body mass index and levels of TG and fasting blood sugar in case group were shown to be higher than control group (P < 0.05), while levels of total cholesterol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol in case group were lower than control group (P < 0.05). Both CC and TC′ + CC frequencies of APOA5 -1131 T > C and APOC3 -455 T > C in case group were higher compared to control group (both P < 0.05). Additionally, T allele frequencies of the two SNPs in case group were lower than control group, while C allele in case group has higher frequencies compared to control group (both P < 0.05). The results of meta-analysis under allele and dominant models showed that APOA5 -1131 T > C and APOC3 -455 T > C SNPs are likely to increase the risk of CHD (both P < 0.05).

Conclusion

APOA5 -1131 T > C and APOC3 -455 T > C SNPs may play potent roles in the development and progression of CHD.

Genetic polymorphism of the estrogen receptor alpha gene and susceptibility to osteoarthritis: evidence based on 15,022 subjects

OBJECTIVE

Several lines of evidence suggest that estrogen receptor alpha (ER-α) gene polymorphism may influence the development of osteoarthritis (OA). However, the results are inconsistent. The aim of this study was to explore using a meta-analysis whether rs2234693 (ER-α PvuII T/C) polymorphism confers significant susceptibility to OA.

METHODS AND RESULTS

A systematic search of all relevant studies published through 17 August 2014 was conducted using the PubMed, Web of Science, Embase, Cochrane database, Current Controlled Trials, Clinicaltrials.gov, Chinese Clinical Trial Registry, CBMdisc, CNKI and Google Scholar. All statistical analyses were done with Review Manager 5.1.4. Twelve articles involving 15 studies were included in the final meta-analysis, which contained 6417 OA cases and 8605 controls. Overall, no significant association was found between the rs2234693 polymorphism and OA risk when all studies were pooled into the meta-analysis (for C allele vs. T allele: OR = 0.99, 95% CI = 0.94-1.04, p = 0.63; for C/C vs. T/T: OR = 0.97, 95% CI = 0.87-1.08, p = 0.53; for C/C vs. T/C + T/T: OR = 0.96, 95% CI = 0.88-1.06, p = 0.43; for C/C + T/C vs. T/T: OR = 1.00, 95% CI = 0.89-1.14, p = 0.94). In the subgroup analysis, significant association was found between the rs2234693 polymorphism and the OA risk in the knee osteoarthritis (KOA) group (for C/C + T/C vs. T/T: OR = 1.15, 95% CI = 1.02-1.29, p = 0.02).

CONCLUSIONS

The present meta-analysis suggests that the rs2234693 polymorphism is associated with an increased KOA risk. Additional well designed genome-wide association studies are required to confirm the result.

Toll-like receptor 4 gene Asp299Gly and Thr399Ile polymorphisms in type 2 diabetes mellitus: a meta-analysis of 15,059 subjects

AIMS

Toll-like receptor 4 (TLR4) gene Asp299Gly and Thr399Ile polymorphisms have been reported to be associated with susceptibility to type 2 diabetes mellitus (T2DM) with inconsistent results. In an effort to clarify earlier inconclusive results, a meta-analysis evaluating the precise associations between TLR4 gene Asp299Gly and Thr399Ile polymorphisms and T2DM risk was performed.

METHODS

We searched the PubMed, Embase, Web of Science, CBMdisc, CNKI, and Google Scholar until July 17, 2014. Additionally, hand searching of the references of identified articles were performed. Original observational studies dealing with the associations between TLR4 gene Asp299Gly and Thr399Ile polymorphisms and T2DM risk were selected. Heterogeneity and publication bias were determined and the meta-analysis was performed by Review Manager 5.1.4 and Stata 11.0.

RESULTS

Seventeen articles involving 25 studies were included in the final meta-analysis, covering a total of 5963 T2DM cases and 9096 controls. For TLR4 gene Asp299Gly polymorphism, 17 studies were combined showing no evidence for association between TLR4 gene Asp299Gly polymorphism and T2DM risk. For TLR4 gene Thr399Ile polymorphism, eight studies were combined. There was also lack of evidence for significant association between TLR4 gene Thr399Ile polymorphism and T2DM risk. In addition, the similar results were obtained in the sensitivity analyses.

CONCLUSIONS

The present meta-analysis indicates that TLR4 gene Asp299Gly and Thr399Ile polymorphisms are not associated with increased T2DM risk.

Association of a genetic variant of the ZPR1 zinc finger gene with type 2 diabetes mellitus

Various loci and genes that confer susceptibility to coronary heart disease (CHD) have been identified in Caucasian populations by genome-wide association studies (GWASs). As type 2 diabetes mellitus (DM) is an important risk factor for CHD, we hypothesized that certain polymorphisms may contribute to the genetic susceptibility to CHD through affecting the susceptibility to type 2 DM. The purpose of the present study was to examine a possible association of type 2 DM in Japanese individuals with 29 polymorphisms identified as susceptibility loci for CHD by meta-analyses of the GWASs. The study subjects comprised of 3,757 individuals (1,444 subjects with type 2 DM and 2,313 controls). The polymorphism genotypes were determined by the multiplex bead-based Luminex assay, which combines the polymerase chain reaction and sequence-specific oligonucleotide probes with suspension array technology. To compensate for multiple comparisons of genotypes, the criterion of a false discovery rate (FDR) ≤0.05 was adopted for testing the statistical significance of the association. The comparisons of allele frequencies by the χ² test revealed that the rs964184 (C→G) of the ZPR1 zinc finger gene (ZPR1) was significantly associated (P=0.0017; FDR=0.050) with type 2 DM. Multivariable logistic regression analysis with adjustment for age, gender and body mass index revealed that rs964184 of ZPR1 was significantly associated (P=0.0012; odds ratio, 1.25; dominant model) with type 2 DM with the minor G allele representing a risk factor for this condition. Fasting plasma glucose levels (P=0.0076) and blood glycosylated hemoglobin contents (P=0.0132) significantly differed among ZPR1 genotypes with the G allele associated with increases in these parameters. ZPR1 may thus be a susceptibility locus for type 2 DM in Japanese individuals.

Association of rs9340799 polymorphism in estrogen receptor alpha gene with the risk of osteoarthritis: evidence based on 8,792 subjects

Osteoarthritis (OA) is one of the most common skeletal disease, which seriously affects the quality of life of patients, particularly in the middle-aged and elderly individuals. We aimed to explore whether rs9340799 [estrogen receptor alpha (ER-α) XbaI A/G] polymorphism was associated with OA using a meta-analysis. A literature search for eligible studies published before March 28, 2014 was conducted in the PubMed, Web of Science, Embase, Cochrane database, Current Controlled Trials, Clinicaltrials.gov, Chinese Clinical Trial Registry, CBMdisc, CNKI, Google Scholar and Baidu Library. The association between the rs9340799 polymorphism and OA risk was assessed by odds ratios (ORs) together with their 95 % confidence intervals (CIs). A total of 663 articles were found. After article review and quality assessment, 10 articles involving 2,924 OA cases and 5,868 controls were included in the final meta-analysis. The combined evidence suggested that rs9340799 polymorphism contributed significantly to an increased risk of OA (for G allele vs. A allele: OR = 1.21, 95 % CI 1.03-1.43, p = 0.02; for G/G vs. A/A: OR = 1.30, 95 % CI 1.07-1.57, p = 0.009). In the subgroup analyses, significant associations were found between the rs9340799 polymorphism and the OA risk in the European group, Asian group, and knee osteoarthritis group, respectively. These results suggested that the rs9340799 polymorphism might be associated with the risk of OA. However, the results should be interpreted with caution because of the publication bias.