Analysis of modifier genes in cystic fibrosis

Cystic fibrosis (CF) is the most common autosomal lethal recessive disease in Caucasoid population, with an estimated incidence of 1 in 5,000 live births. Affected individuals have variants in both copies of the CFTR gene, located on the long arm of chromosome 7, at position 7q31. To date, more than 1,900 mutations of the CFTR gene have been identified, the ΔF508 mutation being the most frequent. Given the diversity of mutations, the wide range of phenotypic variation in CF is not surprising, but this is not due only to the patient’s CFTR genotype, since even patients with the same genotype show a wide range of variability in the severity of the disease. The genetic causes of this variation are being studied and to date various modifying genes have been discovered. Several of them act on important routes for CF and their clinical applications are relatively straightforward.
Therefore, understanding the causes of the variation in the severity of the clinical manifestations of CF is the basis for treating this disease in a personalized way and thus carrying out new and improved therapeutic strategies.