Results for "Kearns-Sayre syndrome."
Conditions Encyclopedia Entry 1777262884
** This encyclopedia entry is about **Mitochondrial Myopathies**, a group of rare genetic disorders affecting the mitochondria, the energy-producing structures within cells. **CONTENT:** ### Overview Mitochondrial Myopathies (MM) are a group of rare genetic disorders that affect the mitochondria, the energy-producing structures within cells. These disorders are caused by mutations in the mitochondrial DNA, which is separate from the DNA found in the cell's nucleus. Mitochondrial myopathies can affect various parts of the body, including the muscles, brain, and other organs. The symptoms of MM can vary widely, depending on the specific type of disorder and the severity of the mutation. Mitochondrial myopathies are often inherited in an **autosomal dominant** pattern, meaning that a single copy of the mutated gene is enough to cause the disorder. However, some types of MM can be inherited in an **autosomal recessive** pattern, requiring two copies of the mutated gene to cause the disorder. The disorders can also occur spontaneously, without a family history. The symptoms of MM can be diverse and may include muscle weakness, fatigue, exercise intolerance, and muscle pain. In some cases, the disorders can lead to more severe symptoms, such as seizures, vision loss, and hearing loss. The disorders can also affect the brain, leading to cognitive impairment, dementia, and other neurological problems. ### History/Background Mitochondrial myopathies were first identified in the 1960s, when researchers discovered that some patients with muscle weakness and other symptoms had abnormal mitochondria in their muscle cells. Since then, numerous studies have been conducted to understand the genetic and molecular mechanisms underlying these disorders. In the 1980s, researchers discovered that the disorders were caused by mutations in the mitochondrial DNA. This was a significant breakthrough, as it provided a clear understanding of the genetic basis of the disorders. Since then, numerous studies have been conducted to identify the specific genes and mutations responsible for the disorders. ### Key Information Mitochondrial myopathies are a group of disorders that affect the mitochondria, the energy-producing structures within cells. The disorders are caused by mutations in the mitochondrial DNA and can affect various parts of the body, including the muscles, brain, and other organs. There are several types of MM, including: * **Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS)**: This is a severe disorder that affects the brain, muscles, and other organs. * **Myoclonic epilepsy with ragged-red fibers (MERRF)**: This disorder affects the muscles and brain, causing seizures, muscle weakness, and other symptoms. * **Kearns-Sayre syndrome (KSS)**: This disorder affects the muscles, brain, and other organs, causing symptoms such as muscle weakness, vision loss, and heart problems. ### Significance Mitochondrial myopathies are a group of rare genetic disorders that can have a significant impact on patients and their families. The disorders can cause a range of symptoms, from mild muscle weakness to severe neurological problems. Understanding the genetic and molecular mechanisms underlying MM is crucial for developing effective treatments and improving patient outcomes. Researchers are working to identify new genes and mutations responsible for the disorders, as well as developing new therapies to target the underlying causes of the disorders. **INFOBOX:** - Name: Mitochondrial Myopathies - Type: Genetic disorder - Date: 1960s (first identified) - Location: Worldwide - Known For: Rare genetic disorders affecting the mitochondria **TAGS:** Mitochondrial myopathies, genetic disorders, mitochondrial DNA, muscle weakness, exercise intolerance, muscle pain, seizures, vision loss, hearing loss, cognitive impairment, dementia, neurological problems, MELAS, MERRF, KSS, Kearns-Sayre syndrome.
Health & MedicineConditions Encyclopedia Entry 1779253564
** This encyclopedia entry is about **Mitochondrial Myopathies**, a group of rare genetic disorders affecting the mitochondria, the energy-producing structures within cells. **CONTENT** ### Overview Mitochondrial myopathies are a group of rare genetic disorders that affect the mitochondria, the energy-producing structures within cells. These disorders occur when there is a mutation in the mitochondrial DNA, which is responsible for producing energy for the cell. Mitochondrial myopathies can affect various parts of the body, including the muscles, brain, and other organs. The symptoms of mitochondrial myopathies can vary widely, but often include muscle weakness, fatigue, and neurological problems. Mitochondrial myopathies are often inherited in an **autosomal dominant** or **maternal inheritance** pattern, meaning that a single copy of the mutated gene is enough to cause the condition, and it is passed down from the mother. The disorders are relatively rare, affecting approximately 1 in 5,000 people worldwide. However, the exact prevalence of mitochondrial myopathies is difficult to determine due to the lack of a centralized registry and the varying severity of the conditions. ### History/Background The first reported cases of mitochondrial myopathies date back to the 1960s, when researchers discovered that certain types of muscle disease were caused by mutations in the mitochondrial DNA. However, it wasn't until the 1980s that the genetic basis of these disorders was fully understood. Since then, numerous studies have been conducted to better understand the causes, symptoms, and treatment options for mitochondrial myopathies. ### Key Information Mitochondrial myopathies are a heterogeneous group of disorders, and there are several types, including: * **Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS)**: A disorder that affects the brain, muscles, and other organs, causing symptoms such as seizures, muscle weakness, and stroke-like episodes. * **Myoclonic epilepsy with ragged-red fibers (MERRF)**: A disorder that affects the brain and muscles, causing symptoms such as seizures, muscle weakness, and ragged-red fibers in muscle tissue. * **Kearns-Sayre syndrome (KSS)**: A disorder that affects the muscles, brain, and other organs, causing symptoms such as muscle weakness, vision loss, and heart problems. The diagnosis of mitochondrial myopathies is often challenging, as the symptoms can be similar to those of other conditions. A diagnosis is typically made through a combination of clinical evaluation, genetic testing, and muscle biopsy. ### Significance Mitochondrial myopathies are significant because they highlight the importance of mitochondrial function in maintaining overall health. The disorders also underscore the importance of genetic testing and counseling for individuals and families affected by these conditions. **INFOBOX** - **Name:** Mitochondrial Myopathies - **Type:** Rare genetic disorders - **Date:** 1960s (first reported cases) - **Location:** Worldwide - **Known For:** Rare genetic disorders affecting the mitochondria **TAGS:** Mitochondrial myopathies, genetic disorders, mitochondrial DNA, autosomal dominant, maternal inheritance, muscle weakness, fatigue, neurological problems, MELAS, MERRF, KSS, Kearns-Sayre syndrome.