CFTR and cystic fibrosis: Figure 1 presents the common CF-related CFTR mutations of >1% frequency in population worldwide. The most common CF-associated mutation is F508del, an example of a Class 2 processing-defect mutation. F508del accounts for approximately two-thirds of CF alleles (66.8%) (Bobadilla et al., 2002). The other common mutations include G542X (2.6%, Class 1), N1303K (1.6%, Class 2), G551D (1.5%, Class 3), W1282X (1.0%, Class 1) (Zvereff et al., 2014; Chamayou et al., 2020; Scotet et al., 2020a; Scotet et al., 2020b; Petrova et al., 2021; Yiallouros et al., 2021).