Association of TLR9 gene polymorphisms with lupus nephritis in a Chinese Han population

Although increasing data have supported the possible role of TLR-9 in the pathogenesis of lupus nephritis (LN), the effect of TLR-9 on the lupus phenotype remains controversial. The aim of this study was to associate common variants in the TLR9 gene with susceptibility to lupus nephritis in the Chinese population to further ascertain whether it is a susceptible locus for SLE, especially its likely role in LN from a comparatively large population.

Two previously reported SLE associated single nucleotide polymorphism (rs352139, rs352140) were investigated in a case-control study comprised of 315 patients with biopsy proven lupus nephritis and 338 matched healthy controls. Single nucleotide polymorphisms (SNPs) were typed by TaqMan allele discrimination assays.

Both rs352139 (p=0.040, OR: 0.713, 95%CI: 0.516-0.985) and rs352140 (p=0.048, OR: 0.723, 95%CI: 0.525-0.997) were associated with LN in dominant model. A trend for an association between genotypes and the disease activity indexes was observed. However, no significance was achieved.

The present study suggested that TLR9 gene have a role in establishing an autoimmune background and pathogenesis in human LN.