Association of single-nucleotide polymorphisms in FOXP3 gene with systemic lupus erythematosus susceptibility: a case-control study.

Foxp3, encoded by the human FOXP3 gene, is a transcription factor that regulates regulatory T-cell (Treg) development and function. Associations have been reported between FOXP3 gene variants and autoimmune endocrinopathy and non-endocrine autoimmune disease. The aim of this study was to investigate the possible influence of single nucleotide polymorphisms (SNP) in the FOXP3 gene on genetic predisposition to systemic lupus erythematosus (SLE). The study cohort comprised 172 SLE patients and 181 controls, who were genotyped for the FOXP3 gene variants. Of five SNPs identified, the FOXP3 -6054 ATT carrier was shown to be associated with renal disorder (odds ratio [OR] 3.26, 95% confidence interval [95% CI] 1.33-8.03, p = 0.0077). Furthermore, lower anti-dsDNA levels were found in patients with the -3279 A carrier (p = 0.0109). To the authors' knowledge, this is the first study to investigate the association of FOXP3 SNPs with susceptibility to SLE, as well as sub-phenotype susceptibility. Although the exact role of Foxp3 and FOXP3 gene variations in SLE is still not clear, the present data support the importance of variations in the FOXP3 gene region for the etiology of certain manifestations of SLE.