Interleukin-7 receptor single nucleotide polymorphism rs6897932 (C/T) and the susceptibility to systemic lupus erythematosus.

Emerging evidences were accumulated to support the view that aberrant interleukin-7 (IL-7) signaling might be associated with autoimmunity. Former studies demonstrated the single nucleotide polymorphism (SNP) rs6897932 C/T in the IL-7 receptor (IL-7R) gene was associated with susceptibility to autoimmune diseases, including multiple sclerosis and type I diabetes. Given these, this study was conducted to investigate whether an association existed between SNP rs6897932 and the susceptibility to systemic lupus erythematosus (SLE), a severe systemic autoimmune disease. In this context, 816 SLE patients and 816 controls from a Chinese population were recruited for this study, and the results showed that the major allele C of rs6897932 showed a higher frequency in SLE patients compared with controls (P = 0.039, C versus T); significant difference was also detected under a recessive model with regard to the distribution of genotype frequencies between SLE patients and controls (P = 0.041, CC versus CT + TT), which was not consistent with the results under a dominant model (P = 0.349, CC + CT versus TT). Moreover, association studies were also performed contraposing the relationship between the SNP rs6897932 C/T and lupus nephritis as well as 10 clinical features of SLE; however, no significant association signal was found regarding the distribution of allele and genotype frequencies between SLE patients positive and negative for the presence of 11 sub-phenotypes. In conclusion, the major allele C of SNP rs6897932 may be associated with increased SLE risk in Chinese populations, and further studies are still encouraged to shed light on the true associations between SLE and its susceptibility genes with respect to IL-7R gene.