EIF2AK4 and pulmonary venoocclusive disease: Three African American and 16 Caucasian patients, including 1 with pulmonary veno-occlusive disease and 1 with pulmonary capillary hemangiomatosis, had mutations in the bone morphogenetic protein receptor type 2 (BMPR2), Caveolin 1 (CAV1) or EIF2AK4 gene.