NKX2-1 and lung disorder: Thyroid transcription factor-1 reportedly regulates SFTPC transcription directly or by connecting the transcriptional co-activator with the PDZ-binding motif.[14] In fact, the combination of 2 mutations can damage pulmonary SP homeostasis and gas exchange, lower oxyhemoglobin saturation, and cause recurrent pulmonary infection and rapid progression of lung disease.