Cystic fibrosis (CF) is a genetic disorder characterized by chronic pulmonary infection primarily with *Pseudomonas aeruginosa*. The disease is caused by mutations in the *CFTR* gene, leading to defective chloride ion transport in epithelial cells. CF patients often present with chronic respiratory infections and gastrointestinal abnormalities, resulting in malabsorption and nutritional deficits. The diagnosis of CF is typically made clinically, with sweat tests being the "gold standard" for confirmation. The *CFTR* gene was identified in 1989, and over 1,000 mutations have been identified, with the ΔF508 mutation being the most common. These mutations affect the function and expression of the *CFTR* protein, leading to a range of clinical manifestations. The epidemiology of CF varies by population, with the ΔF508 allele being particularly prevalent in certain regions. Studies have explored potential heterozygote advantages, such as protection against certain infections, but results are mixed. The role of *CFTR* mutations in the development of lung disease in CF patients is complex and influenced by various factors, including the timing and setting of infection acquisition.Cystic fibrosis (CF) is a genetic disorder characterized by chronic pulmonary infection primarily with *Pseudomonas aeruginosa*. The disease is caused by mutations in the *CFTR* gene, leading to defective chloride ion transport in epithelial cells. CF patients often present with chronic respiratory infections and gastrointestinal abnormalities, resulting in malabsorption and nutritional deficits. The diagnosis of CF is typically made clinically, with sweat tests being the "gold standard" for confirmation. The *CFTR* gene was identified in 1989, and over 1,000 mutations have been identified, with the ΔF508 mutation being the most common. These mutations affect the function and expression of the *CFTR* protein, leading to a range of clinical manifestations. The epidemiology of CF varies by population, with the ΔF508 allele being particularly prevalent in certain regions. Studies have explored potential heterozygote advantages, such as protection against certain infections, but results are mixed. The role of *CFTR* mutations in the development of lung disease in CF patients is complex and influenced by various factors, including the timing and setting of infection acquisition.