Polymorphism of the apolipoprotein B gene and association with plasma lipid and lipoprotein levels in the Mongolian Buryat

Association between Apo B, LDL-R and PCSK9 gene polymorphisms with coronary artery diseases in Egyptians

BACKGROUND

Many studies have focused on the significance of lipid regulatory genes in the pathophysiology of Coronary artery disease (CAD). ApoB XbaI (rs693) and EcoRI (rs1042031) single nucleoid polymorphisms (SNPs) were investigated to detect whether they are risk factors for CAD. Till now, this association remains uncertain. SMARCA4 (rs1122608) SNP has directly related to dyslipidemia. Loss of function mutations (LOF) in PCSK9 result in a reduction in LDL cholesterol and are associated with protection from the development of CAD.

METHODS

This study was conducted on 54 CAD patients who were admitted at Internal Medicine Specialized Hospital (Cardiology Department) and 47 healthy controls. Peripheral blood samples were taken from both groups. DNA was extracted from EDTA-blood samples, then PCR- RFLP for ApoB XbaI (rs693) and EcoRI (rs1042031), SMARCA4 (rs1122608) and PCSK9 (rs505151) SNPs was done.

RESULTS

No statistically significant difference was found between patients and controls as regard EcoRI SNP. XbaI (rs693) X + X + genotype was significantly higher in control group (P = 0.0355). SMARCA4 (TT, GT + TT) genotypes, and T allele (P < 0.001); PCSK9 AG genotype and G allele (P = 0.027 and 0.032 respectively) were more frequent in CAD patients than controls.

CONCLUSION

SMARCA4 (rs1122608) and PCSK9 (rs505151) SNPs are significantly accompanying with the risk of CAD development in the Egyptian population. X + X + genotype appeared to have a protective effect against CAD. However, no observed association between EcoRI (rs1042031) and the risk of CAD development was found.

Deletion allele of Apo B gene is associated with higher inflammation, oxidative stress and dyslipidemia in obese type 2 diabetic patients: an analytical cross-sectional study

BACKGROUND

We decided to compare some inflammatory, and oxidative stress markers, as well as lipid profiles between the obese and non-obese patients with type 2 diabetes considering ApoB gene polymorphism.

METHODS

one-hundred sixty two patients with type 2 diabetes were included in this study. ApoB genotyping was conducted by the polymerase chain reaction. Serum interleukin-(IL-18), pentraxin-3 (PTX-3), and high sensitive- C reactive protein (hs-CRP) was measured as the inflammatory markers. Moreover, copper-zinc superoxide dismutase (Cu/Zn-SOD), total antioxidant capacity (TAC) and 8-isoprostane F2α were analyzed for oxidative stress assessment. Anthropometric indices and lipid profiles were measured.

RESULTS

Adjusted for confounders, serum hs-CRP (p = 0.04), LDL-C (p = 0.01), LDL-C/HDL-C (p = 0.04), and TG (p = 0.02) were significantly lower at the Homozygous Insertion (Ins)/Ins vs. deletion (Del) allele carriers in the obese patients. Serum TAC was significantly lower at the obese Del allele carriers than Ins/Ins Homozygous (p = 0.03). Serum hs-CRP (p = 0.006), and 8-IsoprostanF2α (P = 0.04) were significantly higher in the obese Del allele carriers than non-obese. Serum Cu/Zn-SOD was significantly higher in the non-obese Del allele carriers than obese (p = 0.04).

CONCLUSION

Inflammation, dyslipidemia, and oxidative stress are higher in the Obese Del allele carriers with type 2 diabetes which prone them to other chronic disorders.

Polymorphisms in Genes of Lipid Metabolism Are Associated with Type 2 Diabetes Mellitus and Periodontitis, as Comorbidities, and with the Subjects' Periodontal, Glycemic, and Lipid Profiles

BACKGROUND

Type 2 diabetes mellitus (T2DM) and periodontitis (P) commonly occur as comorbidities, but the commonalities in the genetic makeup of affected individuals is largely unknown. Since dyslipidemia is a frequent condition in these individuals, we investigate the association of genomic variations in genes involved in lipid metabolism with periodontal, glycemic, lipid profiles, and the association with periodontitis and T2DM (as comorbidities).

METHODS

Based on clinical periodontal examination and biochemical evaluation, 893 subjects were divided into T2DM+P (T2DM subjects also affected by periodontitis, n = 205), periodontitis (n = 345), and healthy (n = 343). Fourteen single-nucleotide polymorphisms (SNPs) were investigated: LDLR gene (rs5925 and rs688), APOB (rs676210, rs1042031, and rs693), ABCC8 (rs6544718 and 6544713), LPL (rs28524, rs3735964, and rs1370225), HNF1A (rs2650000), APOE (rs429358 and rs7412), and HNF4A (rs1800961). Multiple linear and logistic regressions (adjusted for covariates) were made for all populations and stratified by sex and smoking habits.

RESULTS

Individuals carrying APOB-rs1042031-CT (mainly women and never smokers) had a lower risk of developing periodontitis and T2DM (T2DM+P); altogether, this genotype was related with healthier glycemic, lipid, and periodontal parameters. Significant disease-phenotype associations with gene-sex interaction were also found for carriers of APOB-rs1676210-AG, HNF4A-rs1800961-CT, ABCC8-rs6544718-CT, LPL-rs13702-CC, and LPL-rs285-CT.

CONCLUSIONS

Polymorphisms in lipid metabolism genes are associated with susceptibility to T2DM-periodontitis comorbidities, demonstrating gene-sex interaction. The APOB-rs1042031 was the most relevant gene marker related to glucose and lipid metabolism profiles, as well as with obesity and periodontitis.

Impact of genetic variants of ABCB1, APOB, CAV1, and NAMPT on susceptibility to pancreatic ductal adenocarcinoma in Chinese patients

BACKGROUND

Among the different types of cancer, pancreatic cancer, particularly pancreatic ductal adenocarcinoma (PDAC), is the most lethal malignancy, with poor early detection rates and prognosis. The aim of the present study was to investigate the potential genetic effects of the single-nucleotide polymorphisms (SNPs) in ABCB1 (rs1045642, rs3789243, rs4148737), APOB (rs693, rs1042031), CAV1 (rs12672038, rs1997623, rs3807987, rs7804372), and NAMPT (rs9034, rs2505568, rs61330082) on PDAC.

METHODS

A total of 273 patients with PDAC and 263 healthy controls were genotyped using PCR and direct Sanger sequencing. Unconditional logistic regression models were used to evaluate the potential effects of the genotypes, alleles, and haplotypes on the risk of developing PDAC.

RESULTS

Patients with PDAC possessed a considerably lower frequency of genotypes AG, GG, and allele G at ABCB1 rs4148737 compared with controls. Based on age, sex, smoking status, drinking status, diabetes, and family history of cancer, stratified analyses showed a significant correlation between SNPs at rs4148737 and PDAC. According to specific SNPs, eight haplotypes were constructed along with ABCB1 rs4148737, rs1045642, and rs3789243. Carriers with haplotypes ACC and ATC were more susceptible to developing PDAC, whereas haplotypes GCC and GTC were associated with a reduced likelihood of developing PDAC. The distributions of the other SNPs in each group were not significantly associated with PDAC risk.

CONCLUSIONS

These results suggested that genetic polymorphisms of ABCB1 rs4148737 may influence an individual's risk of developing PDAC.

The APOB rs693 polymorphism impacts the lipid profile of Brazilian older adults

The apolipoprotein B (APOB) gene contains several polymorphic sites described as risk modifiers for cardiovascular events. The objective of this study was to verify the association of the classic APOB Xba I polymorphism (rs693) with atherosclerotic risk factors in a segment of the Brazilian elderly population considering their usual dietary intake. Clinical and biochemical characteristics as well as total caloric and fat intake data were determined from 644 elderly individuals. Polymorphism analysis was performed by conventional polymerase chain reaction followed by enzyme restriction. Statistical analyses compared measures and proportions according to different APOB genotypic combinations. Statistically significant association was found between Xba I polymorphism and serum LDL, total cholesterol, and total lipid levels, with important elevations among T homozygotes compared to the other genotypes. There was homogeneity in all other parameters analyzed (including intake pattern), with a tendency for reduced levels of circulating apolipoprotein B among TT individuals. Our results pointed out that genetic variation in APOB affected the lipemic profile of elderly individuals in a context not biased by diet, generating a pattern suggestive of secretory disorder of lipoprotein particles, with possible implication in atherosclerotic risk.

Distribution of polymorphism rs693 of ApoB gene in a sample of Colombian Caribbeans

INTRODUCTION

Several studies have reported that the single nucleotide polymorphism rs693 of Apo lipoprotein B gene is associated with high levels of plasma lipids and high body mass index, which are risk factors for cardiovascular diseases. The distribution of this single nucleotide polymorphism and its association with the phenotype depend on the genetic background of each population.

OBJECTIVE

To evaluate the distribution of single nucleotide polymorphism rs693 and its association with lipid profile and body mass index in a sample of Colombian Caribbeans.

METHODS

108 non-related adult subjects of both gender were included in this study. Body mass index and lipid profile that included total cholesterol, triglycerides, Low Density Lipoprotein and High Density Lipoprotein were determined. The single nucleotide polymorphism rs693 was determined by Polymerase Chain Reaction/Restriction Fragment Length Polymorphism from genomic DNA followed by digestion with the restriction enzyme XbaI. The chi-square test was used to analyze the genotype distribution of rs693 and the genotype-phenotype association was evaluated through different inheritance model.

RESULTS

The genotype frequencies for single nucleotide polymorphism rs693 were CC (45.0%), TT (16.5%) and CT (38.5%). The allele frequencies were C (64.0%) and T (36.0%). The single nucleotide polymorphism was in Hardy-Weinberg equilibrium in the studied sample. No association of the single nucleotide polymorphism rs693 with lipid profile nor the body mass index was found (p >0.05).

CONCLUSION

There is no significant association between single nucleotide polymorphism rs693 and body mass index nor lipid profile, in a sample of Colombian Caribbeans.

Associations of the APOB rs693 and rs17240441 polymorphisms with plasma APOB and lipid levels: a meta-analysis

BACKGROUND

The associations of the apolipoprotein B gene (APOB) rs693 and rs17240441 polymorphisms with plasma levels of APOB and lipids have been widely explored, but the results were inconclusive. This meta-analysis aimed to clarify the associations of the rs693 and rs17240441 polymorphisms with fasting APOB and lipid levels.

METHODS

Sixty-one studies (50,018 subjects) and 23 studies (8425 subjects) were respectively identified for the rs693 and rs17240441 polymorphisms by searching in PubMed, Google Scholar, Web of Science, Cochrane Library, Wanfang, VIP and CNKI databases. The following information was collected for each study: first author, age, gender, ethnicity, health condition, sample size, genotyping, lipid assay method, mean and standard deviation or standard error of APOB and lipid variables by genotypes. A dominant model was used for this meta-analysis.

RESULTS

The carriers of the rs693 variant allele (T) had higher levels of APOB [standardized mean difference (SMD) = 0.26, 95% confidence interval (CI) = 0.16-0.36, P < 0.01], triglycerides (TG) (SMD = 0.12, 95% CI = 0.05-0.20, P < 0.01), total cholesterol (TC) (SMD = 0.24, 95% CI = 0.17-0.30, P < 0.01) and low-density lipoprotein cholesterol (LDL-C) (SMD = 0.22, 95% CI = 0.14-0.30, P < 0.01), and lower levels of high-density lipoprotein cholesterol (HDL-C) (SMD = -0.06, 95% CI = -0.11-0.01, P = 0.01) than the non-carriers. The carriers of the rs17240441 deletion allele had higher levels of APOB (SMD = 0.13, 95% CI = 0.06-0.20, P < 0.01), TC (SMD = 0.17, 95% CI = 0.07-0.26, P < 0.01) and LDL-C (SMD = 0.15, 95% CI = 0.07-0.23, P < 0.01) than the non-carriers.

CONCLUSIONS

The rs693 polymorphism is significantly associated with higher levels of APOB, TG, TC and LDL-C, and lower levels of HDL-C. The rs17240441 polymorphism is significantly associated with higher levels of APOB, TC and LDL-C. Further studies are needed to elucidate the underlying mechanisms.

Association analysis of APO gene polymorphisms with ischemic stroke risk: a case-control study in a Chinese Han population

This study aimed to assess the association of APO gene polymorphisms and ischemic stroke risk in a Chinese Han population. In this case-control study, we genotyped 14 single nucleotide polymorphisms (SNPs) in 3 APO genes in 488 cases and 503 controls using Sequenom Mass-ARRAY technology and evaluated their association with ischemic stroke using the χ2 and genetic model analysis. In the allelic model analysis, we determined three SNPs were significantly associated with ischemic stroke: rs693 with a p value of 0.042 (OR = 1.406; 95%CI = 1.011-1.956), rs651821 with a p value of 0.007 (OR = 0.760; 95%CI = 0.622-0.929) and rs662799 with a p value of 0.006 (OR = 0.755; 95%CI = 0.618-0.923). In the genetic model analysis, we found the minor allele “A” of rs693 was associated with an increased ischemic stroke risk in the additive model and dominant model. The minor allele “C” of rs651821 was associated with a decreased ischemic stroke risk in the additive model. The minor allele “G” of rs662799 was associated with a decreased ischemic stroke risk in the additive model. Additionally, strong linkage was found in 3 blocks constituted by rs1042034, rs676210, rs693, rs673548 in APOB; rs3791981, rs679899 in APOB; and rs651821, rs662799, rs17120035 in APOA5. Our data suggested that gene polymorphisms in the APO genes may exert influences ischemic stroke susceptibility in a Chinese Han population.

The genome of a Mongolian individual reveals the genetic imprints of Mongolians on modern human populations

Mongolians have played a significant role in modern human evolution, especially after the rise of Genghis Khan (1162[?]-1227). Although the social cultural impacts of Genghis Khan and the Mongolian population have been well documented, explorations of their genome structure and genetic imprints on other human populations have been lacking. We here present the genome of a Mongolian male individual. The genome was de novo assembled using a total of 130.8-fold genomic data produced from massively parallel whole-genome sequencing. We identified high-confidence variation sets, including 3.7 million single nucleotide polymorphisms (SNPs) and 756,234 short insertions and deletions. Functional SNP analysis predicted that the individual has a pathogenic risk for carnitine deficiency. We located the patrilineal inheritance of the Mongolian genome to the lineage D3a through Y haplogroup analysis and inferred that the individual has a common patrilineal ancestor with Tibeto-Burman populations and is likely to be the progeny of the earliest settlers in East Asia. We finally investigated the genetic imprints of Mongolians on other human populations using different approaches. We found varying degrees of gene flows between Mongolians and populations living in Europe, South/Central Asia, and the Indian subcontinent. The analyses demonstrate that the genetic impacts of Mongolians likely resulted from the expansion of the Mongolian Empire in the 13th century. The genome will be of great help in further explorations of modern human evolution and genetic causes of diseases/traits specific to Mongolians.

Genetic association of APOB polymorphisms with variation in serum lipid profile among the Kuwait population

BACKGROUND

Several studies have identified APOB as a candidate gene predisposing individuals to dyslipidemia. Polymorphisms including the signal peptide (rs11279109), codon 2488 XbaI (rs1042031), codon 3611 MspI (rs693), codon 4154 EcoRI (rs1801701) and the 3' variable number of tandem repeats have been reported to be associated with dyslipidemia in several populations. With limited studies on Arabs, this study aimed to investigate the genetic association of APOB polymorphisms and assess the potential influence of minor and rare alleles on serum lipid levels in the Kuwaiti population.

METHODS

A total of 795 Kuwaiti subjects, documented with phenotypic data and fasting serum lipid levels, were genotyped for the five polymorphisms using PCR, PCR-RFLP and gene fragment analysis. Genotype and allele association with variation in serum lipid levels as well as haplotypes were analyzed using chi-square test, univariate and logistic regression analysis.

RESULTS

Analysis of the genotype and allele frequencies distribution revealed a significant positive association between the APOB signal peptide and 3611 MspI polymorphisms with increased levels of triglycerides (statistical power of 80%). Haplotype analysis further supported the findings by showing that carriers of haplotypes (IX-M-E+M) had significantly lower mean (SD) TG levels (0.86 ± 0.07) as compared to non-carriers (1.01 ± 0.02). Significance was also observed with regards to positive family history of hypercholesterolemia.

CONCLUSION

The results imply a "protective role" for two alleles (rs11279109 and rs1801701) in which logistic regression analysis showed a significant half-fold decrease in the risk for heterozygotes of rs11279109 and an 8.8 fold decrease in the risk for homozygous M-M- of rs1801701 of having lower TG levels (<1.70 mmol/L) in individuals. This suggests that genetic interaction between various polymorphisms at different gene loci act in linkage disequilibrium to affect serum TG levels. Apo B genotyping may be a useful adjunct for the identification of individuals at risk of developing dyslipidemia in order to provide them with lifestyle modifications and/or pharmacological intervention to mitigate the effects of gene interaction and environmental influence.

Correlation between the Xba I polymorphism of apoB gene and serum lipid profiles in Li ethnic group

OBJECTIVE

To study correlation between the Xba I polymorphism of apoB gene and plasma lipid profiles in Li ethnic group.

METHODS

Total 151 cases of healthy Li people were recruited randomly by cluster sampling and 200 Han people were recruited as control; blood was drawn to analyze Xba I polymorphism distribution of apoB gene and serum lipid levels.

RESULTS

There were lower serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) levels in serum of Li people; while, high density lipoprotein cholesterol (HDL-C), X-/X+ genotype and X+ allele frequencies exhibited higher levels than Han people. Interestingly, HDL-C level was reduced, while LDL-C level was enhanced in subjects carrying heterozygous (X-/X+) genotype compared to homozygous (X-/X-) genotype. Additionally, there were no difference in serum level of triglyceride, TC, apoprotein A (apo A) and apoprotein B (apo B) between Li and Han people, the same results were showed between X-/X+ and X-/X- genotype carriers.

CONCLUSIONS

Xba I polymorphism of apoB gene is correlated to the profiles of serum lipid level, X-/X+ genotype carriers are phenotyped with higher LDL-C level and lower level of HDL-C in Li ethnic group.

Associations of polymorphisms of rs693 and rs1042031 in apolipoprotein B gene with risk of breast cancer in Chinese

BACKGROUND

Lipid synthesis is an integrated result of genetic, epigenetic and environmental factors, and also can promote growth and survival of cancer cells. Apolipoprotein B plays a central role in lipid metabolism as the major protein component of very-low-density lipoprotein and low-density lipoprotein.

METHODS

We investigated the associations of polymorphisms of rs693 (-7673C>T) and rs1042031 (-12669 G>A) in the APOB gene with risk of breast cancer in 675 blood-unrelated Chinese patients with breast cancer and 712 healthy controls.

RESULTS

Polymorphisms of -12669 G>A and -7673C>T in the APOB gene were significantly associated with an increased risk of breast cancer (P = 0.000), especially for postmenopausal women (P = 0.000, 0.023). The positive associations still remained after further analysis of the two polymorphisms' distribution according to body mass index. However, no statistical associations were found between -12669 G>A and -7673C>T polymorphisms and other clinical characteristics, including tumor size, lymph node metastasis, histological grade, estrogen and progesterone receptor status and Her-2 status.

CONCLUSIONS

rs693 and rs1042031 polymorphisms in the APOB gene increased the risk of breast cancer in Chinese, and this role of the two polymorphisms in connection with breast cancer was not dependent on body mass index.