STAT1 and vitiligo: CD8+ T cells produce interferon gamma (IFNγ), which is a cytokine destroying the melanocytes.6 Recent work analyzing IFNγ signaling suggests that ligation of IFNγ receptors leads to activation of signal transducer and activator of transcription 1 (STAT1) and eventually transcription of IFNγ-induced gene.5,6 A recent study showed cluster of differentiation 4 (CD4+) T cell played an important role in vitiligo pathogenesis.