Definition
A genetic disease or hereditary disease is a disease whose cause lies in one or more genes of the affected person. In this case, the DNA acts as a direct trigger for the disease. For most genetic diseases, the triggering gene locations are known.
If a genetic disease is suspected, the respective diagnosis can therefore be made by genetic testing. On the other hand, however, there are also a large number of diseases where a genetic influence exists or is discussed, such as diabetes mellitus (“diabetes”), osteoporosis or depression. These are so-called dispositions, i.e. an increased probability of certain diseases. Dispositions must be distinguished from hereditary diseases.
These are common hereditary diseases
Hereditary diseases are not common in absolute numbers, but the hereditary diseases listed here occur frequently in comparison to other diseases of genetic cause. Marfan’s syndrome sickle cell anemia haemophilia (haemophilia A or B) Factor V Leiden mutation and resulting APC resistance red-green weakness glucose-6-phosphate dehydrogenase deficiency (G6PD deficiency) polydactyly (“multitasking”, also possible as a symptom in other diseases) trisomy 21 (Down syndrome) Huntington’s disease
- Marfan syndrome
- Sickle cell anaemia
- Haemophilia (haemophilia A or B)
- Factor V Leiden mutation and resulting APC resistance
- Red-green weakness
- Glucose-6-phosphate dehydrogenase (G6PD) deficiency
- Polydactyly (“polyphagia”, also possible as a symptom in other diseases)
- Trisomy 21 (Down syndrome)
- Chorea Huntington
Causes
Hereditary diseases are extremely diverse in their appearance. Basically, they have only one thing in common: the cause of each of them lies in the DNA, i.e. in the genetic material of the person concerned. Various changes can occur, such as mutations (exchange of DNA information) or deletions (absence of certain genetic material).
A great deal of information is encoded in the genetic material, such as the “blueprints” for various components that are important for the functioning of a body cell. These can be enzymes, electrolyte channels or messenger substances, for example. These smallest elements are then read incorrectly or not at all from the DNA, which is then missing from the body’s sophisticated system. The incorrect or missing genetic information thus causes certain malfunctions in the body. These then cause symptoms corresponding to the functional system in which an element is now missing.
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