Cystic Fibrosis
Cystic fibrosis is one of the most well-known genetic diseases and is very feared because of its consequences. The cause is merely a diseased gene, which leads to a so-called “chloride channel” (CFTR channel) being shaped incorrectly. As a result, numerous cells and organs of the body produce highly viscous secretions, which can lead to lung diseases, intestinal diseases and pancreatic disorders in particular.
The gene is inherited recessively, which means that the disease only occurs if both parents pass the diseased gene on to the child. In pre-existing cases of the disease, the parents can have themselves tested in the family to see whether they carry the diseased gene and can potentially pass it on to the child. The different types of mutations can usually be found in a genetic test and allow a more precise statement about the severity of the disease.
Thus, it is a less severe case if the channel has a poor conductivity than if it is not functional at all. These differences sometimes make a difference in the treatment and can also give an indication of life expectancy in cystic fibrosis and later transplants. Even today, with optimal therapy, the average life expectancy is only 40 years. The most common case is a DeltaF508 mutation, in which the number of channels is reduced and function is impaired.
Lactose intolerance
A genetic test can only be of limited help in detecting lactose intolerance. The test can very reliably diagnose a congenital, primary lactose intolerance where the lactose-cleaving enzyme called lactase is defective. However, a genetic test is of little use in cases of lactose intolerance or secondary lactose intolerance.
These clinical pictures are caused, for example, by damage to the intestine, which can no longer produce sufficient lactase. There is therefore no defect in the lactase gene which could be found in this way. Therefore, conventional examination methods such as the H2 breath test should be used first. As a rule, however, the clinical symptoms and the improvement in symptoms when lactose is avoided are sufficient for diagnosis.
All articles in this series:
- Genetic test – When is it useful?
- These hereditary diseases can be determined by genetic testing
- Implementation
- Costs of a genetic test
- Breast cancer – What does BRCA mean?
- Genetic test for colorectal cancer
- Determine parentage and origin
- Cystic Fibrosis
- Can rheumatism be detected in the genetic test?
- Estimate the risk of thrombosis in a genetic test?
