Growth differential factor‐15 (GDF‐15), asymmetric dimethylarginine (ADMA), endothelial‐1 (ET‐1), vascular endothelial growth factor (VEGF), and surfactant protein‐D (SP‐D) concentrations were found to change significantly in infants with PHT.15, 18, 20, 21, 22, 23. This evidence concerns the gene GDF15 and pulmonary hypertension, primary, 1.