Overall, the findings of this study let them make a conclusion that increased CYP1B1-mediated estrogen metabolism promotes the development of PAH, likely via the formation of mitogens, including 16α-hydroxyestrone.61 In the following year, Yvonne and research group assessed the role of CYP1B1 in the development of PAH induced by an anorectic drug called dexfenfluramine (Dfen) in female mice. The gene discussed is CYP1B1; the disease is pulmonary arterial hypertension.