The TLR7 7926A>G polymorphism is associated with susceptibility to systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a systemic autoimmune disorder that predominantly affects women of childbearing age, with a female-to-male ratio of approximately 9:1. Previous findings indicated that male cases of SLE were associated with Klinefelter's syndrome (47, XXY), whereas females with Turner's syndrome (45, X0) did not contract SLE. Additionally, duplicated Toll-like receptor 7 (TLR7) was found to promote lupus-like disease. Consequently, the aim of this study was to evaluate whether the TLR7 gene served as a genetic marker for the development of SLE. A case-control study was performed on one tag single nucleotide polymorphism TLR7 rs1634323 in a population with 507 SLE patients and 513 healthy controls. Genotyping was determined by the TaqMan genotyping assay using the ABI 7300 real-time reverse transcription polymerase chain reaction system. The results showed a significantly elevated risk of SLE with the rs1634323 AG genotype in females (P=0.040, OR=1.897, 95% Cl 1.031-3.491), whereas a similar association was not replicated in males (P=0.303, OR=0.338, 95% Cl 0.043-2.656). In a subgroup analysis by clinical manifestation of lupus nephritis, no significant differences were found. These findings indicate that the TLR7 gene rs1634323 polymorphism may contribute to SLE susceptibility in females.