Association Between Toll Like Receptor 9 Gene Polymorphism And Susceptibility To Systemic Lupus Erythematosus In Hubei Han Population

Backgrounds Systemic lupus erythematosus（SLE）is a chronic autoimmune disease involving multiple organs and systems.Its clinical manifestations are varied,common in skin and mucosal lesions,more serious can involve joints,blood system,kidney,respiratory system,heart and brain,at any time will cause life danger,leading great damage to the physical and mental health of patients^[1-4].The clinical course of SLE is difficult to predict,which makes the diagnosis and treatment of SLE a great challenge for clinicians.So far,the etiology of SLE is complex and uncertain.A large number of studies have shown that the etiology of SLE is related to genetic,environmental,endocrine,infection and other internal and external factors.Genetic factors play an irreplaceable role in the susceptibility and clinical manifestations of disease.Therefore,in the study of SLE susceptibility,the analysis of human genome-wide susceptibility loci should not be ignored.It has been confirmed that Toll like receptor9（TLR9）plays a key role in the autoimmune response of SLE patients.It promotes the formation of autoantibodies and autoimmune complexes by participating in multiple inflammatory pathways.In the single nucleotide polymorphisms（SNPs）loci of TLR9,rs187084 and rs352140 are located in the promoter and exon regions respectively,which regulate the time,degree and product of gene expression.Therefore,the two loci are the first to study the relationship between the single nucleotide polymorphism of TLR9 and the susceptibility of SLE in the Han population of Hubei Province.To provide clues on gene level for exploring therapeutic targets of SLE in order to improve the diagnosis and prognosis of SLE.Methods PCR amplification of the peripheral blood gene fragment of 80 patients with SLE and 84 healthy volunteers was used to detect the genotype and allele frequency of the two loci of rs187084 and rs352140 by SNa Pshot.Results The AA,GG,and AG genotype frequencies of rs187084 in SLE experimental group and healthy control group were 37.50%,18.75%,43.75%and 47.62%,13.10%,39.29%,respectively（P>0.05）.The genotype frequencies of rs352140 AA,GG,and AG were 18.75%,43.75%,37.50%and 11.90%,48.81%,39.29%in the experimental group and the control group,respectively,with no statistical difference（P>0.05）.Conclusion The single nucleotide polymorphisms of rs187084 and rs352140 loci in TLR 9 may not be associated with the pathogenesis of SLE.