CF is mainly caused by mutations in the cystic fibrosis transmembrane conductance regulator gene.227 In the initial stage, the microbiota of patients with cystic fibrosis is mainly P. aeruginosa, Haemophilus influenzae (H. influenzae), Staphylococcus aureus (S. aureus), Burkholderia cepacia, and Stenotrophomonas maltophilia. This evidence concerns the gene CFTR and cystic fibrosis.