Heterozygous deletions and point mutations in the FOXF1 gene locus were found in patients with Alveolar Capillary Dysplasia with Misalignment of Pulmonary Veins (ACD/MPV), a rare congenital disorder characterized by severe defects in development of the alveolar capillary network. The gene discussed is FOXF1; the disease is alveolar capillary dysplasia with misalignment of pulmonary veins.