While other genes have been identified as having roles in lung development, this master gene, called Foxa2, controls key factors that allow the lungs of a fetus to develop fully and eventually breathe air. While Foxa2 was previously known to exist, its role in lung maturation and function at birth were not known.
When Foxa2 is missing in newborn mice, respiratory distress syndrome and in many cases, death, was almost certain to follow, said Jeffrey A. Whitsett, MD, chief of Neonatology, Perinatal and Pulmonary Biology at Cincinnati Children's and senior author of the study that appears in the October 5 issue of the Proceedings of the National Academy of Sciences (PNAS).
"It was surprising to us that a single gene was able to orchestrate so many other aspects of lung function we know are critical for survival at the time of birth. The discovery of this gene and understanding of how it works could lead to new treatments for premature infants and for children and adults who suffer from lung disease or injury," he said.
Because lungs do not fully mature until the last trimester of gestation, when an infant is born prematurely, the lungs are not fully developed and lack the necessary amount of surfactant needed to keep the lungs working properly. Surfactant is a natural chemical found in the lungs that prevents alveoli - the tiny airways in the lungs - from collapsing and in turn allows the lungs to open when the newborn starts to breath. The absence of surfactant causes respiratory distress syndrome within hours of birth.
"We showed that Foxa2 regulates a group of genes that stabilize surfactant production, which is required for the transit
Contact: Amy Reyes
Cincinnati Children's Hospital Medical Center