Severe vision problems usually begin in the teens or early 20s. Other symptoms, including movement disorders and dementia, vary among patients and occur at different ages. Mitochondria, the tiny power generators in cells, may play a more important role in human health than scientists and doctors have realized, Koehler believes. Each human cell contains several hundred mitochondria that burn food and produce most of the cell's energy. People think mitochondria just produce energy and that we have known everything about them for years, but we're only starting to understand all of the things they do.
Mitochondria tell cells when to live and die, and control cell growth.
They are the 'forgotten' part of the cell. Other inherited mitochondrial diseases probably have been misdiagnosed or overlooked that are really caused by defects in mitochondrial protein import. Symptoms of mitochondrial diseases are typically found in tissues that have high-energy requirements. Such diseases should affect nerves and muscles because they are especially energy-hungry. As we age, our mitochondria become less efficient, which could lead to heart problems, as well as loss of hearing and vision, said Koehler, whose future research may help answer whether such health problems are caused by an inability to properly assemble mitochondria.