Under the term "mitochondrial diseases" include disorders with heterogeneous characteristics. In general, it indicates a group of inherited genetic diseases caused by mitochondria malfunction. The latter are the "energy centers" of the cells. When they do not work properly, they cause disturbances that can involve different tissues.
Mitochondria have their own DNA, susceptible to alterations other than that of nucleotide DNA. Mitochondrial diseases are the result of these alterations and are hereditary, even if they follow their rules. At the time of fertilization, the new individual inherits the mitochondria only from the egg cell. For this reason, diseases of this type are often inherited only by the mother.
Most mitochondrial diseases affect the muscles and the brain. In fact, it is the tissues that most need energy and therefore suffer the most from it. Usually these two forms of mitochondial diseases occur with anemia, pancreatic dysfunctions and cardiac disorders. Often the children who suffer from it show slow growth, deafness and diabetes. Adults tend to get tired soon.
Heterogeneity of symptoms makes diagnosis of mitochondrial diseases difficult. Usually the suspicion arises from the presence of symptoms with progressive course in unrelated organs. The definitive diagnosis comes by finding the deficiency of certain proteins, essential for producing energy. In recent years, the use of genetic tests and prenatal screening tests has also spread. The latter are useful in the presence of family cases.
To date there is no cure for mitochondrial diseases. In some cases it is possible to make up for the deficit of certain substances. There are also medicines useful for reducing the most debilitating symptoms and slowing the progression of the disease.