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Assciation of the TRIB1 and TRPS1 Polymorphisms with Serum Lipid Levels in the Guangxi Jing and Han PopulationsBackground: Dyslipidemia is an important component of metabolic syndrome and an important risk factor for the occurrence and development of atherosclerotic cardiovascular disease(ASCVD).Studies have shown that abnormal lipid metabolism such as the elevated total cholesterol(TC),triglycerides(TG),low density lipoprotein cholesterol(LDL-C)and apolipoprotein(Apo)B levels and / or the decreased high density lipoprotein cholesterol(HDL-C)and Apo A1 levels are closely related to the occurrence and development of ASCVD.Dyslipidemia is known to be a complex disease affected by environmental factors,genetic factors,and their interactions.Studies have shown that the genotypic frequency of the same genetic locus variation and its relationship with the lipid profile may be different in different races and different populations.Therefore,knowing the serum lipid level of a specific population and exploring the influence of certain genetic factors on serum lipid level and controlling it are of great significance for the prevention and treatment of cardiovascular and cerebrovascular diseases in this population.In recent years,several large genome-wide association studies(GWASes)have identified some new gene loci that may be related to serum lipid levels,including tribbles pseudokinase 1(TRIB1)and transcriptional repressor GATA binding gene 1(TRPS1).Later in other populations,researches also show that TRIB1 and TRPS1 single nucleotide polymorphisms(SNPs)are related to serum lipid levels,but the results are inconsistent among different study populations.However,it is not clear whether TRIB1 and TRPS1 are related to lipid level in the population of southwest China,and whether the relationship is ethnic and gender specific.Objectives: To understand the distribution and differences of serum lipid levels between Jing and local Han populations in Guangxi,and to explore the relationship between TRIB1 and TRPS1 SNPs and environmental factors with serum lipid levels in the two ethnic groups.Methods: In the previously stratified random sample library,1133 cases of Jing residents(554 men and 579 women;experimental group)and 1144 local Han residents(567 men and 577 women;control group)were randomly selected as the research objects.The selected population was confirmed by human genetic methods(the study of Y chromosome and mitochondrial diversity).Previous epidemiological surveys were conducted in accordance with international standard methods,and stratified(age and gender)randomly selected three generations of ancestors belonged to the Jing or Han nationalities selected as the research objects.The study subjects were all adults aged ? 18 years.Questionnaires and physical examinations were performed.Fasting blood was drawn and serum TC,TG,HDL-C,LDL-C,Apo A1 and Apo B values were measured.Extract whole blood DNA and 6 SNPs of TRIB1 and TRPS1(TRIB1 rs2954029,TRIB1 rs2980880,TRIB1 rs10808546,TRPS1rs231150,TRPS1 rs2737229 and TRPS1 rs10505248)were genotyped by polymerase chain reaction and restriction fragment length polymorphism(PCRRFLP).The genotyping results were verified by Sanger sequencing.The distribution of TRIB1 and TRPS1 SNPs genotypes and alleles was analyzed.The association of genotypes,haplotypes,and environmental factors with serum lipid levels in both populations was assessed.Results: There were differences in serum lipid levels between the Guangxi Jing and the local Han populations.Serum TC and TG levels were significantly higher in the Jing population than in the Han population,whereas Apo A1 levels and the Apo A1/Apo B ratio were significantly lower in Jing than in Han populations(P <0.05).The genotypic and allelic frequencies of the five SNPs(rs2954029,rs2980880,rs231150,rs2737229,and rs10505248)were different between the Jing and Han ethnic groups(P < 0.05).The genotypic and allelic frequencies of rs2954029 and rs10808546 SNPs in Han ethnic group were different between male and female subgroups,while the genotypic and allelic frequencies of rs231150 and rs10505248 SNPs in Jing ethnic group were also different between male and female subgroups(P < 0.05).In the Han population,the levels of TC(rs2954029,rs231150 and rs2737229),TG(rs2954029 and rs10808546),LDL-C(rs2954029),HDL-C(rs2980880,rs10808546 and rs231150),and Apo A1(rs2737229)were significantly different between the minor allele carriers and non-carriers(P < 0.008,6 SNPs corrected by Bonferroni);among the Jing population,the levels of TC(rs2954029and rs2737229),TG(rs10808546),HDL-C(rs2954029,rs231150 and rs10505248),and Apo A1(rs231150)were statistically significant different between the minor allele carriers and non-carriers.In Han men,there were statistically significant differences in TC(rs10808546 and rs231150),HDL-C(rs2980880,rs10808546 and rs231150)and Apo A1(rs2737229)levels between the minor allele carriers and noncarriers.Among the Han women,there were statistically significant differences in TG(rs2954029 and rs10808546),LDL-C(rs2954029),Apo B(rs10808546)and Apo A1/Apo B(rs10808546)levels between the minor allele carriers and non-carriers.In Jing men,there were statistically significant differences in TC(rs2954029,rs10808546 and rs2737229),LDL-C(rs2954029)and HDL-C(rs231150 and rs10505248)levels between the minor allele carriers and non-carriers(P < 0.008,6SNPs corrected by Bonferroni).Linkage disequilibrium(LD)analysis showed that there was LD among the three TRIB1 SNPs in the two nationalities(D' > 0.5).The haplotype of T-T-C(in the order of rs2954029,rs2980880 and rs10808546)was the most common haplotype.The frequencies of T-T-C,A-C-C,T-T-T and A-T-C haplotypes were statistically significant differences between the two nationalities.Serum TC(T-T-C and A-C-C),TG(A-T-C)and HDL-C(T-T-T)levels in the Han population were statistically significant differences between the haplotype carriers and non-carriers.Serum TC(T-T-C and A-C-C),TG(T-T-T)and HDL-C(T-T-C and A-T-C)levels in the Jing population were also statistically significant differences between the haplotype carriers and non-carriers(P < 0.0125,4 haplotypes corrected by Bonferroni).Multiple regression analysis showed that serum lipid levels in both Han and Jing populations were closely corelated to environmental factors such as gender,age,body mass index,waist circumference,smoking,drinking,blood pressure and blood glucose(P < 0.05).Conclusions: There are different in serum lipid levels between Jing and local Han populations in Guangxi.The association between SNPs of TRIB1 and TRPS1 and serum lipid levels in Han and Jing may have ethnic/gender specificity.The three TRIB1 SNPs have strong LD,and the association between the haplotypes and serum lipid levels have ethnic differences.In addition,serum lipid levels are closely corelated to environmental factors such as gender,age,body mass index,waist circumference,smoking,drinking and blood pressure.The differences in serum lipid profiles between the two ethnic groups may be partly due to genetic differences in the TRIB1 and TRPS1 and differences in some environmental factors.Part ? Associaton of the TRIB1 and TRPS1 Polymorphisms,Gene-Gene and Gene-Environment Interactions with Coronary Heart Disease and Ischemic StrokeBackground: Coronary heart disease(CHD)and ischemic stroke(IS)are still the major causes of morbidity and death worldwide,causing severe economic and social burdens.Their common pathological basis is atherosclerosis,and dyslipidemia is an important independent risk factor for atherosclerosis.Both CHD and IS are complex diseases affected by multiple factors including genetics,environment and gene-environment interactions.GWASes in European populations and subsequent studies in other populations have reported that TRIB1 and TRPS1 polymorphisms are related to blood lipid levels.In our previous studies,we also found that TRIB1 and TRPS1 polymorphisms are related to serum lipid levels in the Guangxi Jing and Han populations.However,there are fewer studies on the relationship between TRIB1 and TRPS1 polymorphisms and the incidence of CHD and IS.Objectives: To investigate the association of TRIB1 and TRPS1 SNPs,genegene and gene-environment interactions and the incidence of CHD and IS in the Han population in Guangxi.Methods: A case-control study was conducted among the Han population in Guangxi,and a total of 1771 samples were collected,including 625 normal healthy controls,553 CHD patients,and 593 IS patients.Three SNPs of TRIB1(TRIB1 rs2954029,TRIB1rs2980880 and TRIB1 rs10808546)and three SNPs of TRPS1(TRPS1 rs231150,TRPS1 rs2737229 and TRPS1 rs10505248)were selected as the research sites.An epidemiological survey was conducted on the study subjects and related biochemical indicators such as serum lipid levels were tested.Genotyping was performed by PCR-RFLP method,and genotyping results were verified by Sanger direct sequencing.The distribution of genotypes and alleles in the case and the control groups was compared,and the effects of the genotype,haplotype,genegene and gene-environment interactions on the incidence of CHD and IS were analyzed.The association of genotypes and serum lipid levels was analyzed in the normal control group.Results: The genotypic and allelic frequencies of TRIB1 rs2954029 and TRPS1 rs231150 SNPs were significantly different between the CHD and control groups;and the genotypic and allelic frequencies of TRIB1 rs2954029 and TRIB1rs2980880 SNPs were also significantly different between the IS and control groups(P < 0.05).After the Bonferroni correction(6 SNPs,P < 0.008 were considered statistically significant),the genetic models of genotypes for the incidence of CHD were statistically significant: co-dominant model(rs2954029,AA vs.TT,OR = 1.80,95% CI = 1.34-2.62,P = 0.0024);dominant model(rs2954029,TA/AA vs.TT,OR = 1.52,95%CI = 1.18-1.97,P = 0.0011;rs231150,TA/AA vs.TT,OR = 1.48,95%CI = 1.14-1.92,P = 0.0035)and log-additive model(rs2954029,A vs.T,OR = 1.36,95%CI = 1.14-1.63,P < 0.001;rs231150,A vs.T,OR = 1.36,95%CI = 1.14-1.63,P = 0.0015).The genetic models with statistical significance for the risk of IS were: dominant model: TA/AA vs.AA(rs2954029,OR = 1.48,95%CI = 1.14-1.90,P = 0.0026);and log-additive model: A vs.T(rs2954029,OR = 1.30,95%CI = 1.09-1.55,P = 0.0039).In both case and control groups,there was strong LD among the TRIB1 rs2954029,TRIB1 rs2980880 and TRIB1 rs10808546 SNPs(D' > 0.8),and the haplotype of T-T-C(in the order of rs2954029,rs2980880 and rs10808546)was the most common haplotype.Haplotype of A-C-C increased the risk of CHD(OR = 1.37,95%CI = 1.11-1.70,P = 0.0036)and IS(OR = 1.31,95%CI = 1.06-1.61,P = 0.01).Haplotype of A-T-C increased the risk of CHD(OR = 1.63,95%CI = 1.25-2.13,P < 0.001).rs2954029TA/AA-age(> 60 years)interaction increased the incidence of CHD,while rs10808546CT/TT-drinking interaction reduced the risk of IS(P < 0.0017,6 SNPs and 5 environmental factors corrected by Bonferroni).The influence of TRIB1 and TRPS1 loci on the incidence of CHD and IS exists gene-gene interaction.Rs2954029-rs231150 has a strong interaction on the risk of CHD and IS.Rs2954029-rs231150-rs10808546 and rs2954029-rs231150-rs10808546-rs2737229 have weak interactions on the risk of CHD;Rs2954029-rs231150-rs10808546 and rs2954029-rs231150-rs10808546-rs2980880 have weak interactions on the risk of IS.In the normal control group,genotype was associated to serum lipid levels.Carriers of the minor alleles of the following SNPs have higher TC(rs2954029 and rs231150),TG(rs2954029 and rs10808546),LDL-C(rs2954029),HDL-C(rs2980880),and Apo A1(rs2737229)levels than the minor allele non-carriers;and the carriers of the minor alleles of the following SNPs have lower TC(rs2737229)and HDL-C(rs231150)levels than the minor allele non-carriers(P < 0.008,6 SNPs corrected by Bonferroni).Conclusions: The genotypic and allelic frequencies of TRIB1 and TRPS1 SNPs were significantly different between the case and control groups(CHD,rs2954029 and rs231150;IS,rs2954029 and rs2980880).Carriers of the rs2954029 A and rs231150 A alleles increased the risk of CHD,and carriers of the rs2954029 A allele increased the risk of IS.Haplotypes of A-C-C and A-T-C increased the incidence of CHD,and Haplotype of A-C-C also increased the risk of IS.Rs2954029TA/AA-age(> 60 years)increased the risk of CHD,whereas rs10808546CT/TT-drinking interaction reduced the incidence of IS.TRIB1 and TRPS1 interactions affect the risk of CHD and IS.TRIB1 and TRPS1 SNPs may influence the risk of CHD and IS in partly by influencing serum lipid levels.Gene-gene and gene-environment interactions affect the risk of CHD and IS.Part ? Screening of Molecular Markers for DNA Methylation in HyperlipidemiaBackground:With the development of social economy and improvement of living standard,the serum lipid level of the Chinese population is gradually increasing,and the prevalence of hyperlipidemia is increasing.Hyperlipidemia is a kind of abnormal lipid metabolism disease that seriously endangers human health,and it is a major risk factor for ischemic cardiovascular and cerebrovascular diseases based on the pathophysiology of atherosclerosis.Therefore,it is particularly important to find the molecular markers for the prevention and treatment of hyperlipidemia.Previous studies have found that methylation of promoter regions of genes related to lipid metabolism can affect insulin regulation,serum high-density lipoprotein levels,and the risk of coronary heart disease.In addition,many studies have shown that DNA methylation plays a regulatory role in many important biological processes,affecting the occurrence and development of diseases.Therefore,the study of hyperlipidemia from the perspective of DNA methylation provides us with a new idea.At present,it has not been reported that hyperlipidemia has been studied from genome-wide DNA methylation level.Objectives: Using Illumina Infinium Methylation EPIC Bead Chip(850K chip)and Methyl Target detection technology,combined with bioinformatics analysis,to screen molecular markers of DNA methylation related to hyperlipidemia.Methods: Five patients with hyperlipidemia were selected as the case group and five healthy adults as the normal control group.Fasting blood was drawn and related biochemical indicators such as serum lipid levels were tested.DNA was extracted from whole blood,and 850 K chips were used to analyze the differences in methylation levels in the peripheral blood of the hyperlipidemia group and the normal control group.Bioinformatic was used for data analysis to screen candidate genes for DNA methylation level differences in patients with hyperlipidemia.The expanded sample included 60 patients with hyperlipidemia and 60 healthy normal controls.Methyl Target sequencing technique was used to detect the target Cp G regions and Cp G sites methylation level of candidate gene promoter region in hyperlipidemia group and normal group.Results: A total of 1,838 differential methylation sites were screened through 850 K chip,corresponding to 921 genes(P < 0.05,the absolute value of the degree of differential methylation is greater than 0.1).Gene ontology(GO)enrichment analysis was conducted to describe the functions of differentially methylated genes,involving 64 items of biological processes of statistical significance,48 items of cellular components,and 13 items of molecular functions.The enrichment analysis of Kyoto encyclopedia of genes and genomes(KEGG)involved 59 pathways of statistical significance.Six candidate genes: insulin receptor(INSR),angiopoietin 1(ANGPT1),lysophosphatidic acid receptor 1(LPAR1),membrane-associated guanylate kinase inverted 2(MAGI2),platelet-derived growth factor C(PDGFC) and Phospholipase D1(PLD1)were screened for differential methylation related to lipid metabolism.Further verification showed that the methylation levels of the Cp G regions and Cp G sites in INSR,MAGI2 and PDGFC promoter region in the hyperlipidemia group were higher than those in the normal control group with statistically significant differences(P < 0.05).Conclusions: Through 850 K chip and Methyltarget detection technology,combined with bioinformatic analysis,it was found that the methylation levels of Cp G regions and Cp G sites in the promoter region of INSR,MAGI2 and PDGFC genes were higher than those in the normal control group.These three genes may be the DNA methylation molecular markers of hyperlipidemia. |
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