CFTR and cystic fibrosis: To date, over 2100 CFTR mutations have been described (Cystic Fibrosis Mutation Database, https://www.genet.sickkids.on.ca/ (accessed on 10 May 2022)), of which currently 401 are confirmed to cause CF (Clinical and Functional Translation of CFTR (CFTR2), https://www.CFTR2.org/ (accessed on 10 May 2022)).