The detection of biallelic pathogenic EIF2AK4 mutations is able to make precise and accurate molecular diagnoses of autosomal recessively inherited pulmonary capillary hemangiomatosis (PCH) and pulmonary veno-occlusive disease (PVOD), and this was documented in the 6th World Symposium on Pulmonary Hypertension [6]. The gene discussed is EIF2AK4; the disease is pulmonary arterial hypertension.