Indeed, in vivo screens using zebrafish are becoming more commonplace66, 67 and given the description of a CF‐relevant phenotype in the Cftr KO zebrafish by Bagnat and colleagues,17 a phenotypic screen of chaperone protein targets of potential benefit as therapeutic targets for CFTR folding mutants could be envisioned. The gene discussed is CFTR; the disease is cystic fibrosis.