Background: Vitiligo is an autoimmune disorder characterized by loss of pigmentation from the skin due to selective destruction of cutaneous melanocytes. Its pathogenesis is linked to regulatory T-cell (Treg) dysfunction. Forkhead box P3 (FOXP3) is a specific Treg marker and a master regulator of its activity. Objective: The purpose of this study was to examine the relationship between serum levels of FOXP3 in Egyptian vitiligo patients and single-nucleotide polymorphisms (SNPs) at two distinct loci (rs3761548) A/C and (rs2232365) A/G situated in the promoter region of the FOXP3 gene. Patients and methods: The study comprised 50 untreated vitiligo patients who attended the dermatology clinic at Benha University Hospitals, and 30 age- and sex-matched healthy controls. Polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) was used to identify FOXP3 gene polymorphism, and a FOXP3 enzyme linked immunosorbent assay (ELISA) was used to assess the quantity of FOXP3 in the blood. Results: Highly significant difference (P |