For example, CRISPR/Cas9 repair of CFTR mutations in cystic fibrosis patient-derived intestinal organoids restored ion channel function, while retinal organoids were corrected for mutations linked to inherited blindness, demonstrating its potential for degenerative diseases (Yin et al., 2016; Nie and Hashino, 2017). Here, CFTR is linked to cystic fibrosis.