['Persistent pulmonary hypertension of the newborn (PPHN) is associated with substantial infant morbidity and mortality. Recently, genetic associations have been found in idiopathic pulmonary arterial hypertension.', 'PPHN was significantly (P < 0.05) associated with genetic variants in corticotropin-releasing hormone (CRH) receptor 1, CRHR1 and CRH-binding protein, CRHBP. Association with CRHR1 rs4458044 passed the Bonferroni threshold for significance. No mutations were found in the bone morphogenetic protein receptor type II (BMPR2) gene.'] Are variations in CRHR1 associated with persistent pulmonary hypertension of the newborn?