Previously, we identified a single nucleotide polymorphism (SNP) in the arginase‐1 (ARG1) gene, rs2781666 (T‐allele) that was associated with a decreased risk for developing pulmonary hypertension (PH) in a cohort of infants with bronchopulmonary dysplasia (BPD). Here, ARG1 is linked to pulmonary hypertension.