The Association Study Of MiRNA-146a Gene And Its Target IRAK-1 Gene With Systemic Lupus Erythematosus

Systemic Lupus Erythematosus (SLE) is an autoimmunity disease with multiple system impairment(including skin and mucous membrane, blood system, nervous system, joint). SLE character as over actibvate B cells, produce autoimmune disease characterized by massive anti nuclear antibody. It is a polygenic disease, which incidence showed significant familial aggregation. Both gene and environment play important roles in the development of-SLE. In our study, we use Meta analysis to acess the association between small RNA-146a gene (microRNA-146a, miRNA-146a) loci rs2910164 (G/C) and target gene of interleukin-1 receptor associated kinase 1 (interleukin-1 receptor-associated kinase1, IRAK-1) gene rs 1059703 (T/C) and susceptibility to SLE firstly. Then with the help of molecular-biologic techniques including Polymerase Chain Reaction and Restriction Fragment Length Polymorphism, we applied a case-control_study to study gene polymorphism, gene-gene and gene-environment interaction with susceptibility of SLE in the Han Chinese women live in the South of Yangtze River. Furthermore, through the case only study design, study the correlation of miRNA-146a and target gene IRAK-1 polymorphism and SLE phenotype. Finally, get a second Meta-analysis include our study to have a more reliable conclusion.The results are as follows:Part I Meta-analysis of gene polymorphism and SLE1、Meta analysis showed that miRNA-146a gene rs2910164 polymorphism is not related to the susceptibility of SLE. However, more experimental research is needed to confirm this conclusion owning to-the population difference, sample size constraints, homogeneity;2、Meta analysis showed that IRAK-1 gene rs 1059703 polymorphism and autoimmune diseases may be related. In additive model and the dominant model, there was not statistically significant association (TT V CT/CC:OR=0.807,95% CI=0.613-1.063, P=0.127) outside, other models with case-control differences were statistically significant (T V C:OR= 0.818,95%CI=0.721-0.929, P=0.002; CT V CC:OR=0.789, 95% CI=0.666-0.934, P= 0.006; TT vCC:OR=0.693,95% CI= 0.494-0.973, P=0.034; TT/CT V CC:OR=0.777,95%CI=0.661-0.914, P=0.002). But the conclusion is not stable.Part II The association of Single Nucleotide Polymorphism(SNP) with SLE1、The result from univariate logistic regression indicated, there is correlation between rs2910164 polymorphism of miRNA-146a and SLE, C allele as the reference, and G allele carriers has the significantly increased risk of SLE (P=0.003, OR=1.572,95%CI= 1.169-2.114). In the additive and recessive model the polymorphisms is associated with SLE (additive:P=0.003, OR=0.625,95%CI= 0.460-0.848; recessive:P=0.002, OR=2.366,95%CI=1.376-4.071). Takes GG as the reference, individuals with GC decreased SLE risk. Compare to GC\CC genotype carriers, increased susceptibility to GG. But there was no significant difference in the dominant model.2、The result from univariate logistic regression indicated, miRNA-146a gene rs57095329 (A/G), rs6864584 (T/C) polymorphism and SLE doesn’t have significant correlation.3、The result from univariate logistic regression indicated, there is an association between IRAK-1 gene rs 1059703 (T/C) polymorphism and the susceptibility of SLE. And the distribution of-T allele in patient group is lower than in the control group (P<0.001, OR=0.441,95%CI=0.282-0.689). Statistically significant is found in the additive model, TT, TC, CC distribution is different (P<0.001, OR= 2.300, 95%CI=1.457-3.630); under the dominant model, the difference was statistically significant (P<0.001, OR=2.530,95%CI,=1.543-4.149). Compare to-TT/TC genotype, carrying the CC genotype increased SLE risk. Under the recessive model, the association was not found to be statistically significant between the two groups.4、The multiple logistic regression indicated, after adjusting for age and possible risk factors (such as frostbite history, living history, history of exposure to ultraviolet radiation environment is damp, hormone use history, drug allergy history and family history); the correlation between miRNA-146a rs2910164 (G/C) loci and rs1059703 sites of IRAK-1 and SLE still exists, and not obvious altered. MiRNA-146a gene rs57095329 (A/G) locus and susceptibility to SLE is still not related.5、The multiple logistic regression indicated, after adjusting for age and possible risk factors (such as frostbite history, living history, history of exposure to ultraviolet radiation environment is damp, hormone use history, drug allergy history and family history); miRNA-146a, rs57095329 polymorphisms may be associated with SLE, and statistical significance was found in three models (additive models:P=0.007, OR=1.849,95%CI=1.182-2.893; dominant model:P= 0.031, OR=3.478,95%CI= 1.121-10.792, recessive model:P= 0.010, OR=2.081,95%CI=1.189-3.642), and compared with AA individual genotypes, and genotype AG/GG and AG genotype of the individual, the risk of SLE increased; compared with genotype AG/AA, genotype GG individual risk also increases.Part III The association of haplotype and interaction affect with SLE1、Linkage disequilibrium test showed that, miRNA-146a gene loci rs2910164 and rs57095329, rs2910164 and rs6864584, rs57095329 and rs6864584, are all linkage disequilibrium (D’=0.821, r2=0.234, P<0.01;=0.719, r2=0.038, D’ P<0.01 =0.735; D,r2=0.007,P<0.01).2、HAPSTAT 3.1 software was used to analyze the genetic model in three different miRNA-146a haplotypes associated with SLE. The dominant model, carrying the C-A-T haplotype individual compared to not carry this haplotype individuals could lower the risk of SLE (P= 0.049, OR=0.402); in the recessive model, with respect to not carry G-A-T haplotype individuals, individuals with G-A-T increased the risk of SLE (P= 0.021, OR=1.211). According to the AIC minimum principle, prompting a recessive mode of inheritance was the best pattern.3、In Log-line model and logistic regression analysis, no statistically significant gene-gene interaction and gene-environment interactions were found.Part Ⅳ The association of genes polymorphism with SLE phenotype1、The result of χ2 test indicated that, with G allele as the reference, miRNA-146a rs2910164 gene C allele in patients with the joint damage risk increased (x 2 =4.395, P=0.036, OR=1.569,95%CI=1.029-2.393). Taking CC as the reference, the CG distribution is higher in anti RNP in abnormal group (χ2=8.274, P=0.016, OR=2.159,95%CI=1.832-2.604); locus are associated with anti SM (χ2=4.284, P= 0.038), and the allele G in case group were higher than that of C (OR=2.625 95%CI=1.041-6.618).2、The result of χ2 test indicated that, miRNA-146a gene rs57095329 polymorphism and joint damage, kidney damage and neurological damage correlation. And in all lesions, with G as the reference, the A allele was a protective factor (joint:χ2=3.957, P=0.047, OR=0.616,95%CI=0.382-0.995; x2=5.047, kidney:P=0.025, OR=0.579,95%CI=0.358-0.935; nervous system:loss of χ2 =4.412, P=0.036, OR=0.252,95%CI=0.252-0.963). Genotype distribution and anti RNP levels (χ2=18.042, P<0.001), and compared with AG/GG, AA in the level of anti RNP positive group distribution of low (OR=0.088,95%CI=0.024-0.320). Compared with the A allele of the G allele individual anti RNP levels were at greater risk (OR=2.680,95%CI= 1.559-4.605).3、The result of χ2 test indicated that, the relationship between the miRNA-146a gene rs6864584 locus and the IRAK-1 gene rs 1059703 polymorphism and clinical organ damage and immunological indexes, has not yet found a statistically significant association.4、Haplotype analysis showed a correlation between joint damage and C-A-T haplotypes (P=0.025, OR=1.761) under the additive model; secondly, found that C-A-T haplotype and the nervous system injury also have correlation (P=0.014, OR=2.143). The recessive model, find G-A-T haplotype and blood system injury related (P=0.016, OR=2.428), suggesting those who do not carry the G-A-T haplotype may more vulnerable than the haplotype carriers in the possibility of blood system injury.5、Haplotype analysis showed, under the additive model, that C-A-T haplotype and anti SM indicators related (P=0.043, OR=0.598), and C-A-T in the positive group distribution reduced; secondly, the C-A-T haplotype and anti RNP index also has correlation (P=0.023, OR=0.391), distribution and positive group carrying C-A-T haplotypes were also reduce. In the recessive model, showed that there exists a correlation between G-A-T haplotype and the anti SM index (P=0.002, OR=1.840). The dominant model, with respect to not carry C-A-T haplotype of the individual, decrease possibility carrying C-A-T haplotypes anti abnormal RNP levels (P=0.002, OR=0.861).Part V Second Meta-analysis of gene polymorphism and SLE1、The result of the second Meta-analysis shows, miRNA-146a gene rs2910164 site may becorrelation with the presence of SLE in the Asian population. The G allele compared with the C allele is a risk factor (P=0.005, OR= 1.333, 95%CI= 1.089-1.633). Carriers of the GG genotype relative risk carriers GC and CC genotypes of SLE also increased (P=0.001, OR=1.900,95%CI=1.284-2.811). And no relation was found in European population.2、The result of the second Meta-analysis shows, correlation between the miRNA-146a gene rs57095329 and SLE, and compared with the G allele carriers, risk of SLE is lower with individuals carrying A allele (whole population:P<0.001, OR=0.770,95%CI=0.708-0.837; P<0.001, OR=0.780, Chinese:95%CI=0.710-0.856; non Chinese:P=0.001, OR=0.732,95%CI=0.610-0.880).3、The result of the second Meta-analysis shows, IRAK-1 rs 1059703 gene and autoimmune diseases may be related, in the whole population, T allele is a protective factor compared with the C allele (P=0.033, OR=0.770,95%CI=,0.708-0.837); in the dominant model, the TT and TC individuals compared with CC individuals was found to decline the risk of autoimmune disease in the total population (P<0.001, OR=0.780,95%CI=0.710-0.856).