NKX2-1 and interstitial lung disease: Genetic variants of NKX2.1 have been associated with decreased surfactant production contributing to neonatal respiratory distress syndrome and the development of interstitial lung disease.6 The decreased surfactant causes increased alveolar surface tension predisposing to atelectasis, increased ventilation-perfusion mismatch, and increased pulmonary inflammatory response that increase the potential for lung injury.