Investigation On Risk Factors Of Type 2 Diabetes In Xinjiang Uygur Population And Susceptibility Gene Polymorphisms With Its Potential Mechanism

Object:The environmental factors and genetic risk factors of type 2 diabetes mellitus(T2DM)in Xinjiang Uygur population were investigated by either questionnaire and gene sequencing.The environmental risk and protective factors of T2DM were analyzed in Uygur,and to explore the association between gene polymorphism and susceptibility to morbidity of type 2 diabetes mellitus(T2DM).Finally,based on the intron gene polymorphism may affect the gene shear isomerism of this hypothesis,the study of the role of shear isomers with molecules and cells in liver and islet cells is studied.Methods:The experimental design was based on the analysis of case and control study.From March 2013 to December 2015,the first Affiliated Hospital of Xinjiang Medical University and the Fifth Affiliated Hospital,the First Hospital of Kashi District,,at the same time,the 1010 uygur participants who were not diagnosed as diabetes,no blood relationship with any T2DM patients in the family were recruited from the hospital physical examination center as the control group.Systematic information on the socioeconomic,demographic information,personal and family history of disease,smoking,drinking and other environmental factors.In accordance with international standards for human body measurement(height,weight,waist circumference,hip)and blood pressure measurement,and blood lipids and blood sugar,glycosylated hemoglobin and other physiological and biochemical indicators.All data were processed by SPSS 17.0 software package,and the related environmental risk factors of Uygur of type 2 diabetes mellitus were analyzed by logistic regression.Genetic risk analysis,based on the literature,to determine the detection of transcription factors 7 analog 2,TCF7L2(Transcription factor-7-like 2),including 13 T2DM susceptibility gene 30 single nucleotide polymorphisms(Single-nucleotide polymorphisms,SNPs)for blood cell genome sequencing.Multiple polymorphism of each sample was typed by the multiple SNP typing technique(iMLDR?SNP)of Mulitiplex Snapshot.In the Uygur population study,the Hardy-Weinberg imbalance of SNPs was included,and the distribution of genotypes and alleles at each locus was analyzed byχ2 test.Logistic regression was used to analyze the association between environmental factors and genetic polymorphism and Uygur T2DM.HepG2,Hep 3B2.1-7 and human pancreatic islet cells HPDE6-C7,human pancreatic cancer cell lines MiaPaCa-2,PANC-1,BXPC-3,and then confirmed TCF7L2 scissors in human normal liver cell line HL-02,hepatoma cell line HepG2,Hep 3B2.1-7 The effect of TCF7L2 transcripts on the proliferation and apoptosis of TCF7L2 transcripts was determined by cell transfection,MTT and flow cytometry.Finally,rt-qPCR was used to validate TCF7L2 transcripts on humanβ-islet cells(Glucagon-like peptide-1,Glp-1),Cyclin D1,Ccnd1,Insulin and Insulin Promoter(Pancreas/duodenum homeobox protein 1,pdx-1)mRNA expression levels.Results:1.Identify the risk factors of T2DM patients in Uygur Xinjiang Uygur Autonomous Region.A total of 1258(62.6%)males and 752 females(37.4%)were included in this study.The count number of males with T2DM was 630(31.3%),and 380(18.9%)for females were in the case group,628(31.2%)in males and 372 in female were(18.5%)in the control group.There was no significant difference in age(χ2=6.00,P=0.318)and gender(χ2=0.04,P=0.843),but there were significant differences between the two groups in body mass index(BMI)and waist Hip-hip ratio(WHR),educational level and income level,hypertension and nonalcoholic fatty liver disease(NAFLD),coronary heart disease and other related medical history and diabetes family history,drinking and smoking of the participants.It showed that the statiatical significant in the aspect of living habits between two groups(P<0.01).The results of Llogistic regression analysis showed that the high waist-to-hip ratio was a risk factor,and the odds ratio(OR)of type 2 diabetes was 1.019(95%CI:1.005-1.034)),indicating that risk of developing diabetes of a patient with a higher waist circumference raised 1.019 times than a patient with lower a unit of waist circumference.For the factor of the income level,the monthly income of 2000-3500 yuan group,3500-5000 yuan group with the monthly income of 2,000 yuan compared to the group,the risk of diabetes,the two groups and the monthly income of 2000 compared to the ORvalue were Was 2.314(95%CI:1.300-4.118),3.498(95%CI:1.977-6.192).Indicating that in a certain income range,high monthly income but a risk factor.Then we also compared the relevant history such as hypertension,coronary heart disease,NAFLD,family history of diabetes,high fat diet,smoking,drinking,physical exercise and other factors are associated with diabetes.Results show that the high blood pressure,coronary heart disease,family history of DM,NAFLD,drinking OR values were 4.556(95%CI:2.509 8.274),4.039(95%CI:2.333 6.990),6.410(95%CI:3.212 12.789),3.581(95%CI:2.097 6.118),,1.735(95%CI:1.193 2.522)respectively,indicating that hypertension,coronary heart disease,family history of DM,NAFLD,and alcohol are all high risk factors for diabetes.The OR value of smoking and physical exercise were 0.035(95%CI:0.014-0.089)and 0.544(95%CI:0.350-0.843),indicating that smoking and physical exercise were protective factors for diabetes..2.The interaction effect between single nucleotide polymorphisms(SNPs)and related factors on T2DM.among Uygur population.(1)Four polymorphic loci rs290487,rs864745,rs231362 and rs4430796 of the suscepitibility genes TCF7L2(Transcription factor7-like2),HNF1β,JAZF1和KCNQ1,which were consistent with the Hardy-Weinber equilibrium and the minimum allele frequency(MAF),were selected for the further analysis.We found that the genotypes of rs290487,rs864745 and rs231362 rs4430796 in Xinjiang Uygur population were significantly different between T2DM case group and healthy control group(rs290487:X~2=0.350,P=0.840;rs4430796:X~2=1.751,P=0.417;rs864745:X~2=0.000,P=1.000;s231362:X~2=0.073,P=0.972).(2)The difference of distribution of the genetype of four SNPs between the two groups and the stratification analysis by gender.It showed the significant statistical different distribution in rs231362(KCNQ1),rs290487(TCF7L2)、rs4430796(HNF1β)、rs864745(JAZF1)of case amd control group in male and famel Uygur respectively.(3)The analysis of the genetic models with SNPs of the four genes on T2DM.The genetic models of rs231362、rs290487、rs864745和rs231362 showed the significant statistical differences between the two groups.(1)For rs231362 genetype,OR value of GA was 0.394 in the risk of T2DM compared to genetype GG(95%CI:0.225-0.484,P<0.001);OR value of AA was 0.127 in the risk of T2DM compared to GG,95%CI was 0.070-0.228,P<0.001).Results showed that allele model allele A of rs231362 at the risk of T2DM of OR value was 0.351 compare to allele G(95%CI=0.272-0.452,P<0.001).In dominant gene model,OR value of GA+AA was 0.281 at the risk of T2DM compared to GG(95%CI=0.195-0.405,P<0.001).In recessive gene model of rs231362,OR value of AA was 0.229 compared to GG+GA(95%CI=0.132-0.396,P<0.001).(2)For rs290487 genetype,OR value of TC was 0.234 in the risk of T2DM compared to genetype TT(95%CI:0.096-0.570,P<0.001);OR value of CC was 0.066 in the risk of T2DM compared to TT(95%CI:0.027-0.159,P<0.001).Results showed that allele model allele C of rs290487 at the risk of T2DM of OR value was 0.280 compare to allele T(95%CI=0.211-0.372,P<0.001).In dominant gene model,OR value of TC+CC was0.116 at the risk of T2DM compared to TT(95%CI=0.049-0.275,P<0.001).In recessive gene model of rs290487,OR value of CC was 0.226 compared to TC+TT(95%CI=0.158-0.328,P<0.001).(3)For rs4430796 genetype,OR value of GA was 0.586 in the risk of T2DM compared to genetype GG(95%CI:0.397-0.864,P=0.001);OR value of GG was 0.524 in the risk of T2DM compared to AA,95%CI was 0.316-0.871,P=0.007).Results showed that allele model allele G of rs4430796 at the risk of T2DM of OR value was 0.719compare to allele A(95%CI=0.566-0.914,P=0.007).In dominant gene model,OR value of GA+AA was 0.570 at the risk of T2DM compared to GG(95%CI=0.195-0.405,P<0.001).In recessive gene model of rs4430796,OR value of AA was 0.229 compared to GG+GA(95%CI=0.393-0.826,P=0.003).(4)For rs864745 genetype,OR value of TC was 0.523 in the risk of T2DM compared to genetype TT(95%CI:0.357-0.766,P<0.001);OR value of CC was 0.206 in the risk of T2DM compared to TT(95%CI:0.120-0.356,P<0.001).Results showed that allele model allele C of rs864745 at the risk of T2DM of OR value was 0.480 compare to allele T(95%CI=0.376-0.613,P<0.001).In dominant gene model,OR value of TC+CC was0.421 at the risk of T2DM compared to TT(95%CI=0.293-0.606,P<0.001).In recessive gene model of rs864745,OR value of CC was 0.301 compared to TC+TT(95%CI=0.184-0.493,P<0.001).(5)The stratification analysis of the genetic models with SNPs of the four genes on T2DM by genderIt showed the similar results in male Uygur and female Uygur as the Uygur population when the stratification analysis of the genetic models with SNPs of the four loci rs290487,rs864745,rs231362 and rs4430796.Genetype GG and allele G of rs231362(KCNQ1),genetype TT and allele T of rs290487(TCF7L2),genetype AA and allele A of rs4430796,genetype TT and allele T of rs864745(JAZF1)were identified the associated with the risk of T2DM in male and female respectively in Uygur.(4)Interaction of gene functions and the metabolic parameters and living habits on T2DM among Uygur population.The results of the interactions between gene functions and metabolic parameters and living habits showed that the interaction of genetype GA+AA of rs231362(KCNQ1)locus and physical exercise could increase the risk of T2DM in Uygur(P<0.001).The interactions of the genetype CT+TT of rs290487(TCF7L2)and smoking(P=0.004)、drinking(P=0.001)and hypertation(P<0.001)could increase the risk of T2DM respectively.The interactions of genetype TT+TC of rs864745(JAZF1)loci and dyslipidemia(P<0.001)and physical exercise(P=0.008)respectively may play the role in creasing the risk of T2DM in Uygur after adjusting the other factors in logistic regression models.3.The effects of isomers of TCF7L2 on the proliferation and apoptosis of liver and islet cells.TCL7L2 clears isomerism in liver and pancreatic 8 cell lines and demonstrates the presence of exon4 and exon5 exon deletions in cells,in which exon4 and exon5 are absent in HPDE6-C7 cell lines The exosomes were the most obvious,while the ability of human normal hepatocytes HL02 and isletβcells to express exon4 and exon5 exons was relatively weak.However,we did not observe the presence of exon 8 exon in all cell lines.EGFP overexpression vector was transfected into human embryonic hepatocytes HL-02and isletβ-cells.MTT assay was used to detect cell proliferation.Flow cytometry showed that TCF7L2 affected hepatocyte and islet cell proliferation and apoptosis The Compared with wild-type TCF7L2,the TCF7L2 cleavage isomers lack exon4/exon5have reduced the ability of human hepatocyte proliferation,and the protective ability of inhibiting apoptosis is weakened.The TCF7L2 cleavage isomers of wild-type TCF7L2 and exon4/exon5 were not significantly affected by proliferation of human islet cells,but the protective ability of inhibiting TCT7L2 was lower than that of wild-type TCF7L2.When exon4/exon5 was absent,the ability of the cut isomers to enhance the expression of islet cells,such as insulin synthesis genes,is diminished.Conclusion:1.We clearly show that smoking and physical exercise are protective factors,the remaining obesity,high income,high fat diet,drinking,combined with hypertension,coronary heart disease,NAFLD,family history of diabetes are risk factors.2.The distribution of gene loci rs231362(KCNQ1),rs290487(TCF7L2)、rs4430796(HNF1β)、rs864745(JAZF1),showed statistical significant different in Uygur.Genetype GG and allele G of rs231362(KCNQ1),genetype TT and allele T of rs290487(TCF7L2),genetype AA and allele A of rs4430796,genetype TT and allele T of rs864745(JAZF1)were identified the associated with the risk of T2DM in Uygur.3.We found that rs290487,rs231362 and rs4430796 loci could be used as genetic risk or protective factors for the development of T2DM in Chinese Uygur males or females as well as the whole population.Interaction with metabolic parameters and lifestyle characteristics found that these genes were more likely to be found Morality is associated with it.Finally,4.We found that exon4/exon5 deletion of isomers of TCF7L2 in hepatocyte and islet cell lines by molecular cell experiments and that it affected the ability of apoptosis of liver and islet cells.Finally,we found that these deletions Structure may affect islet cell proliferation,insulin synthesis related gene expression.These results demonstrate the environmental and genetic factors of Uygur’s diabetes mellitus,which may provide effective evidence for the future diagnosis and prevention of T2DM in Uygur,and will further study the relationship between polymorphism and TCF7L2 polymorphism The related mechanism lays the pre-theoretical basis.