OBJECTIVETo observe the association between systemic lupus erythematosus (SLE) and gene polymorphisms of OLF-1/EBF associated zinc finger protein(OAZ).METHODSVerified single nucleotide polymorphisms (SNPs) with relatively high heterozygosity were chosen for allelic discrimination in 244 Chinese SLE pedigrees. Then transmissions of single SNP, and haplotypes were calculated by Genehunter software..OAZ mRNA level was also measured for comparing gene expression in patients of different haplotypes.RESULTSGenotyping of five SNPs within OAZ gene introns indicated there was no preferential transmission of single SNP, and haplotype T-A-G-G for rs1344531-rs2080353-rs933564-rs1345431 showed only weak linkage with the disease (P=0.04). However, haplotypes combining SNPs and the SLE-associated D16S517 allele showed significant association with SLE susceptibility (for rs933564-d16s517 G-271bp t:non-t=93:29 P<0.000001, for rs2080353-rs933564-d16s517 A-G-271bp t:non-t=88:35 P=0.000002). The haplotype A-G-271bp-G of Rs2080353-rs933564-D16s517-rs1345431 was also transmitted to patients preferentially (P=0.0084) and it showed a tendency to affect gene expression.CONCLUSIONSpecial polymorphism haplotype of OAZ gene is associated with Chinese SLE. OAZ may suggest a new pathway for lupus.

Background Previous studies have suggested that interrupted clearance of nuclear DNA-protein complexes after cell death might initiate and propagate systemic lupus erythematosus (SLE). Deoxyribonuclease I ( DNase I) may be responsible for the removal of DNA from nuclear antigens at sites of high cell turnover, thus preventing the onset of SLE. The purpose of this study was to genotype the single nucleotide polymorphisms ( SNPs) of DNase1 and characterize its gene expression and alternatively spliced transcripts in Chinese patients with SLE in order to understand the pathogenic role of DNase1 in human SLE.Methods Four SNPs located at the 3' end of the DNase1 gene, as listed on the SNP website, were selected for analysis. Those SNPs with relatively high heterozygosity were chosen for genotyping in 312 Chinese SLE families using the Taqman minor groove binder (MGB) allelic discrimination method. Haplotypes were constructed and linkage disequilibrium tests were performed using GeneHunter. DNase1 mRNA expression was detected using real-time polymerase chain reaction (PCR), and alternatively spliced transcripts were isolated using capillary electrophoresis. Any effects the specific SNP haplotypes had on DNase1 gene expression and the alternatively spliced transcripts were also assessed.Results rs179982 and rs1053874 had high heterozygosity, about 0.5 in this Chinese cohort, while rs1059857 was also found to be heterozygous. Analysis of the haplotype combining rs179982-rs1030874 (C-G) and rs179982-rs1030874-rs1059857 (C-G-G) revealed a skewed transmission in favor of affected offspring. DNase1 gene expression was higher in SLE patients than in normal controls (P < 0.001), but this was not related to disease activity or SNP haplotype. Capillary electrophoresis revealed that the pattern of alternatively spliced transcripts in patients differed from that of normal controls. Furthermore, different SNP haplotype combinations generated different transcript patterns in SLE patients.Conclusions The SNP haplotypes are in linkage disequilibrium in Chinese SLE patients and may induce the disease through a modification of DNase1 mRNA splicing rather than at the level of mRNA expression. There is a relatively unique transcript band in SLE patients independent of special haplotype, which suggests that other unknown factors might be involved in adjusting gene expression.

OBJECTIVE:To observe whether deoxyribonuclease I (DNASE1) gene expression and its DNASE1 mRNA expression was detected by real-time polymerase chain reaction and its alternatively spliced transcripts were performed by capillary electrophoresis. An analysis was also made to disclose whether specific single nucleotide polymorphisms (SNPs) haplotype had effects onDNASE1 gene expression and its alternatively spliced transcripts.RESULTS:DNASE1 gene expression was higher in SLE patients than in normal controls (P<0.001), and in patients it was found to be of no relationship with SLE disease activity index score. However, it was increased in female patients. Capillary electrophoresis revealed that the pattern of alternatively spliced transcripts in patients was not the same as that in normal controls. Moreover, it seemed that different SNPs haplotype combination might show different transcript pattern in SLE patients.CONCLUSION:In SLE patients, DNASE1 gene expression is abnormal and there are alternatively spliced transcripts different from those in normal controls. DNASE1 gene is a critical factor in the pathogenesis of SLE.