Considering, on the one hand, the critical influence of smoking on the incidence, severity and response to treatment in Graves’ orbitopathy and, on the other hand, the very recent demonstration of a reduced miR-199a expression in human gingival fibroblasts exposed to cigarette smoke extract, the impact of smoking on NOX4/HIF-1α/VEGF and miR-199a warrant further investigations. The gene discussed is NOX4; the disease is Graves ophthalmopathy.