9708. Genetics. Cystic fibrosis (gene CFTR)

The genetic test detects mutations in the CFTR gene that cause cystic fibrosis, a severe inherited disorder affecting the respiratory and digestive systems. The test can also identify carrier status in healthy individuals.

Cystic fibrosis is an autosomal recessive genetic disorder caused by mutations in the CFTR (Cystic Fibrosis Transmembrane Conductance Regulator) gene. This gene encodes a protein responsible for transporting chloride ions across epithelial membranes in the lungs, intestines, pancreas, and sweat glands.

As a result of genetic changes, the protein becomes nonfunctional, leading to the accumulation of thick mucus, impaired organ function, and chronic infections.

• Each person has two copies of the CFTR gene: one inherited from the mother and one from the father.
• The disease develops when both copies are mutated.
• People with one mutated copy are carriers – they are healthy but can pass the mutation on to their children.

The most common mutation is ΔF508, but there are more than 1,000 other variants, which may have different levels of clinical significance.

• In the presence of symptoms that may indicate cystic fibrosis:
  • frequent bronchopulmonary infections;
  • chronic cough with sputum production;
  • low body weight despite preserved appetite;
  • pancreatic insufficiency, steatorrhea (fat in the stool);
  • salty-tasting skin (excessive sweating, NaCl).
• For couples planning a pregnancy, especially if one of the partners:
  • has a family history of cystic fibrosis;
  • is a carrier of a CFTR mutation (identified through screening).
• For newborns — if the disease is suspected or if the biochemical newborn screening result is positive.
• Before in vitro fertilization (IVF) — to assess the risk of transmitting the recessive disorder.
• In men with obstructive azoospermia, as CFTR carrier status may be associated with congenital absence of the vas deferens.

• Venous blood

In order to exclude factors that may affect the test results, we recommend to follow the preparation rules: