Association study of TLR-9 polymorphisms and systemic lupus erythematosus in Northern Chinese Han population

• We genotyped 4 common SNPs of TLR9 gene in the case–control study.
• The association of TLR9 gene with SLE was studied in Northern Chinese.
• We found that rs351240, H2 and H3 were associated with SLE in Northern China.
• It may provide a novel pathway for the diagnosis and prognosis of the disease.

BackgroundSystemic lupus erythematosus (SLE) is an autoimmune disease, with multiple genetic and environmental factors involving in its etiology. The toll-like receptor 9 (TLR9) gene has been reported to have important roles in the development and progression of SLE. We performed a case–control study to investigate the effects of 4 SNPs in the TLR9 gene in the development of SLE in Northern Chinese population.MethodsFour SNPs including rs187084, rs5743836, rs352139 and rs352140 were genotyped using the SNaPshot® method. A group of 430 SLE patients were compared to 424 normal controls. Data were analyzed by SPSS 17.0 and HaploView v 4.1 software.ResultsThe frequency distributions of SNP rs351240 and haplotype H2 (TGCT) and H3 (CATT) were found to differ significantly between patient and control groups (p < 0.05), while other SNPs and haplotypes showed no significant difference between the two cohorts (p > 0.05).ConclusionThe results revealed that variations in the TLR9 gene are associated with SLE, indicating that TLR9 may play an important role in the pathogenesis of SLE in the northern Chinese Han population.