Fra-2 TG mice not only develop pulmonary fibrosis, but also reflect several important features of SSc-ILD, including vasculopathy with endothelial cell apoptosis and pulmonary hypertension [18, 19], systemic inflammation predominated by Th2 inflammation [17, 20, 21], followed by fibrosis of skin, lung and other organs [17, 22]. The gene discussed is FOSL2; the disease is pulmonary arterial hypertension.