On animal models of HHT, Paul Oh has elegantly shown that a local injury (e.g. burn wounding of a mouse ear) inflicted on Alk1-deficient mice triggers an abnormal revascularization (with dilated and tortuous vessels resembling HHT arteriovenous malformations) [30]. The gene discussed is ACVRL1; the disease is arteriovenous hemangioma/malformation.