Studies have reported a decrease in the number of CD4+ CD25+ FOXP3+ Treg cells and impaired Treg-cell-mediated suppression in individuals with SLE, and this decrease is inversely correlated with the severity of the disease.50-53 Hence, modulating both the quantity and functionality of Treg cells has emerged as a promising therapeutic option for managing SLE. The gene discussed is FOXP3; the disease is systemic lupus erythematosus.