children s health issues
Mitochondrial Disorders
Introduction
Mitochondrial disorders are a group of Overview of Hereditary Metabolic Disorders that occur when mitochondria do not function correctly in the body. Hereditary disorders occur when parents pass the defective Cells are tiny structures inside cells that provide the cells with energy. Mitochondria are present in every cell except red blood cells. Unlike other structures inside cells, mitochondria have some of their own genetic material that is inherited only from the mother. Other genetic material for the mitochondria is in the cell nucleus with the rest of the cell's genetic material, and children with a disorder must inherit an abnormality from each parent. Mitochondrial disorders cause mitochondria to stop working properly, so that less and less energy is generated within the cells. This may lead to cell injury or even cell death and body systems will not function properly. Mitochondria supply energy to many organs in the body. Some of these organs, such as the brain, nerves, muscles, and retinas, require more energy than others do. These high-energy organs are particularly susceptible to the problems caused by mitochondrial disorders. Depending on which cells are affected, problems include the following: Seizure Disorders None Severely reduced muscle tone (hypotonia, or "floppiness") Weakness of the eye muscles (ophthalmoplegia) Overview of Stroke None Severe Constipation in Adults None Impairment of heart muscles ( Overview of Cardiomyopathy ) When mitochondria do not function properly, a waste product called lactic acid may build up in the bloodstream (called lactic acidosis). This buildup of lactic acid may help distinguish a mitochondrial disorder from other metabolic diseases. The following are examples of mitochondrial disorders. 