CFTR and cystic fibrosis: The vitamin A analog fenretinide corrects the high ω-6/ω-3 (AA/DHA) fatty acid ratio (Guilbault et al., 2009), the ratios of LCC/VLCC ceramide species and mucus production in CFTR KO mouse lung, and plasma lipid imbalance in CF patients (Garic et al., 2017, 2020; Youssef et al., 2020c).