To investigate the intrinsic role of CFTR in metabolic regulation, we generated CFTR–/– (CF pigs) (31) and CFTR+/+ pigs (WT pigs) of both sexes, including 8 pairs of littermates, and assessed the arterial blood metabolome of newborn piglets using liquid chromatography–mass spectrometry (LC-MS) (Figure 1A). This evidence concerns the gene CFTR and cystic fibrosis.