The article considers the issue of cystic fibrosis – a monogenic autosomal recessive disease. It describes the history of the CFTR gene discovery, the further search for modifier genes to explain the variability of the clinical manifestations of cystic fibrosis. The review discusses problems of connective tissue dysplasia and somatic pathology, which is formed due to the connective tissue dysmorphogenesis in patients with cystic fibrosis; and also the article contains justification for the connection between the formation of severe fibrosis of the lungs and liver and the presence of clinical and genetic markers of connective tissue dysplasia. The author assumes that the clinical and genetic polymorphisms of connective tissue influence the course of cystic fibrosis, formation of bronchiectasis, interstitial pneumofibrosis, cystic fibrosis dysplasia, liver fibrosis and cirrhosis.