Leigh syndrome, also known as subacute necrotizing encephalomyelopathy, is a rare genetic disorder that affects the central nervous system. This condition typically begins in infancy or early childhood and is characterized by progressive neurological deterioration.
Leigh syndrome is caused by mutations in certain genes that encode for proteins involved in energy production within cells, specifically in the mitochondria. Mutations in genes such as MT-ATP6, MT-TL1, and others have been identified in patients with Leigh syndrome.
Patients with Leigh syndrome often experience a decline in motor skills, muscle weakness, and difficulty breathing. This can lead to respiratory failure and the need for mechanical ventilation. Other symptoms may include seizures, heart problems, and impaired growth.
The prognosis for individuals with Leigh syndrome is generally poor, with most affected individuals dying within a few years of the onset of symptoms. However, the severity and progression of the condition can vary widely between individuals.
Research into the underlying causes and mechanisms of Leigh syndrome is ongoing. Studies have identified defects in the function of mitochondrial respiratory complexes as a key feature of the condition. Furthermore, it has been suggested that certain mitochondrial DNA variants may predispose individuals to developing Leigh syndrome.
Testing for Leigh syndrome usually involves a combination of genetic testing, metabolic testing, and imaging studies. Identifying the specific genetic mutations involved can help determine the prognosis and guide treatment options.
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Currently, there are no approved treatments for Leigh syndrome, but there are clinical trials and ongoing research aimed at developing potential interventions. It is important for individuals affected by Leigh syndrome and their families to seek out the most up-to-date information and resources, including support from advocacy organizations and medical professionals.
In conclusion, Leigh syndrome is a rare and devastating genetic disorder that primarily affects the central nervous system. It is caused by mutations in genes involved in mitochondrial energy production and is characterized by progressive neurological deterioration. Ongoing research and clinical trials are providing hope for improved understanding and potential treatments for this condition.
Frequency
Leigh syndrome is a rare genetic disorder that is associated with altered mitochondrial function. It is estimated to occur in about 1 in every 40,000 newborns.
According to certain studies, the frequency of Leigh syndrome varies depending on the population being studied. In some populations, it is more common than in others. For example, in certain populations, such as the French-Canadian population of Quebec, the frequency of Leigh syndrome is higher due to a specific gene-encoded variant.
The condition is often first noticed in infancy or early childhood when affected children develop problems with their motor skills, including muscle weakness and difficulty with movement. They may also experience problems with swallowing, heart problems, and cognitive decline.
Research and advocacy groups, such as the Mitochondrial Disease Foundation, provide resources for patients and families affected by Leigh syndrome. They support scientific research into the causes and treatment of the syndrome, as well as clinical trials for potential therapies. These resources are valuable for families looking to learn more about the condition and find support from others going through similar experiences.
Genetic testing can be used to confirm a diagnosis of Leigh syndrome. The most frequently identified gene variants associated with Leigh syndrome are MT-ATP6 and MT-ND5, which encode proteins involved in mitochondrial oxidative phosphorylation.
References to scientific articles and research studies related to Leigh syndrome can be found in databases such as PubMed and ClinicalTrials.gov. Many of these studies focus on identifying the genetic causes of the condition and understanding the underlying cellular and molecular mechanisms involved.
In summary, Leigh syndrome is a rare genetic disorder that is caused by certain gene variants associated with altered mitochondrial function. It affects the brain and muscle cells and often presents with symptoms related to motor skills, swallowing, and heart problems. Genetic testing can be used to confirm a diagnosis, and research and advocacy groups provide valuable resources for patients and families affected by this condition.
Causes
In Leigh syndrome, the most common cause is an altered gene known as MT-ATP6, which is located on chromosome 8 and is inherited in an autosomal recessive pattern. This gene encodes a subunit of ATP synthase, an enzyme complex involved in the energy production process within cells.
Other genetic causes of Leigh syndrome include mutations in various genes encoding proteins involved in mitochondrial function, such as mitochondrial DNA (mtDNA) genes MT-ATP6 and MT-ND5. These mutations can affect the function of respiratory chain complexes, leading to impaired energy production in cells.
It is important for individuals with Leigh syndrome to undergo genetic testing to determine the specific genetic cause of their condition. This information can help guide treatment decisions and provide additional scientific resources for both patients and their families.
In some cases, Leigh syndrome may be caused by environmental factors. For example, exposure to certain toxins or infections during pregnancy can increase the risk of developing this condition.
Although the exact frequency of Leigh syndrome is unknown, it is considered to be a rare condition. Available references suggest that Leigh syndrome occurs in less than 1 in 40,000 live births.
- MT-ATP6 gene mutations: Mutations in the MT-ATP6 gene are associated with Leigh syndrome. These mutations can result in a decrease or loss of ATP synthase function, which affects energy production in cells.
- MT-ND5 gene mutations: Mutations in the MT-ND5 gene, which is part of the mitochondrial DNA, can also cause Leigh syndrome. Similar to MT-ATP6 mutations, these mutations can impair energy production in cells.
- Other genetic causes: There are several other genes that have been associated with Leigh syndrome, including MT-ND1, MT-ND6, NDUFAF2, and SURF1. Mutations in these genes can lead to mitochondrial dysfunction and the development of Leigh syndrome.
- Environmental factors: In some cases, Leigh syndrome may be caused by exposure to certain toxins or infections during pregnancy. These environmental factors can affect the normal development and function of the brain and lead to the development of Leigh syndrome.
It is important for individuals with Leigh syndrome and their families to seek medical attention and genetic counseling. Genetic testing can help identify the underlying cause and provide information about the inheritance pattern and the risk of passing the condition on to future generations.
Research is ongoing to further understand the causes of Leigh syndrome and develop potential treatments. Clinical trials listed on clinicaltrials.gov may provide opportunities for individuals with Leigh syndrome to participate in research studies aimed at finding new therapies.
References:
- Gripp, K. W., & Thorburn, D. R. (2019). Leigh syndrome. [Updated 2020 Jun 18]. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993- available from: https://www.ncbi.nlm.nih.gov/books/NBK320989/.
- Rahman, S., & Thorburn, D. (2019). Mitochondrial medicine: Leigh syndrome. The Journal of Inherited Metabolic Disease, 42(3), 387-395. doi: 10.1007/s10545-019-02095-9.
Learn more about the genes and chromosome associated with Leigh syndrome
Leigh syndrome is a genetic condition that affects the central nervous system. It is caused by mutations in certain genes that encode proteins involved in energy production within cells.
Most cases of Leigh syndrome are caused by mutations in nuclear genes, meaning genes located in the nucleus of cells. These mutations can be inherited from a person’s parents, or they can occur spontaneously. About 75% of cases are caused by mutations in the SURF1 gene. Other genes associated with Leigh syndrome include PDHA1, PDHB, COX10, COX15, and SUCLA2, among others.
Leigh syndrome can also be caused by mutations in mitochondrial DNA. Mitochondria are structures within cells that have their own DNA and are responsible for producing energy. Mutations in mitochondrial DNA can affect the function of proteins involved in energy production and lead to Leigh syndrome. The most common mitochondrial DNA mutation associated with Leigh syndrome is called the MT-ATP6 mutation.
Leigh syndrome is inherited in an autosomal recessive manner, which means that an affected person must inherit two copies of the mutated gene (one from each parent) in order to have the condition. If only one copy of the gene is mutated, the person is typically a carrier and does not have symptoms of Leigh syndrome.
People with Leigh syndrome often experience a range of symptoms, including developmental delays, muscle weakness, poor muscle tone, problems with movement and balance, seizures, respiratory problems, and optic atrophy, among others. The severity and progression of symptoms can vary widely among affected individuals.
Diagnosis of Leigh syndrome is typically based on clinical features, brain imaging findings (such as characteristic lesions), and genetic testing. Genetic testing can help identify specific gene mutations associated with the condition.
For more information about Leigh syndrome and the genes associated with it, you can visit the following resources:
- The Genetic and Rare Diseases Information Center (GARD) – provides information about Leigh syndrome and links to additional resources for patients and families
- OMIM (Online Mendelian Inheritance in Man) – a comprehensive scientific resource that provides information about genes and genetic conditions
- PubMed – a database of scientific articles that can be used to find additional research and information about Leigh syndrome
- ClinicalTrials.gov – a database of clinical trials that are currently underway or recruiting patients for research on Leigh syndrome
These resources can provide more information about the genetic causes of Leigh syndrome, ongoing research, and potential treatment options. In addition, advocacy and support groups for Leigh syndrome can provide valuable resources and support for individuals and families affected by the condition.
Inheritance
Leigh syndrome is a rare genetic disorder that is frequently inherited. It is associated with mutations in genes that encode proteins involved in the mitochondrial respiratory chain, such as mitochondrial ATP synthase and cytochrome oxidase. These mutations impair the normal function of these proteins and disrupt the energy production process in cells.
There are different types of inheritance patterns observed in Leigh syndrome. In some cases, the condition is inherited in an autosomal recessive manner. This means that an affected individual has inherited two copies of the mutated gene, one from each parent. Carriers of a single copy of the mutated gene are generally unaffected.
In other cases, Leigh syndrome can be inherited in an X-linked manner. This means that the mutated gene responsible for the condition is located on the X chromosome. Males have only one X chromosome, so they are more likely to be affected by X-linked Leigh syndrome. Females have two X chromosomes, so they are usually carriers of the mutated gene but may also be affected in rare cases.
In some instances, Leigh syndrome can also occur sporadically, meaning there is no family history of the condition. These cases may be caused by new mutations that occur during the development of the embryo or in the germ cells of the parents.
It is important for individuals with Leigh syndrome or a family history of the condition to seek genetic counseling. Genetic counselors can provide more information about the specific inheritance pattern and the risk of passing on the condition to future generations.
For more information about inheritance patterns and specific genetic mutations associated with Leigh syndrome, resources such as OMIM, PubMed, and clinicaltrials.gov can provide additional articles and research studies.
Other Names for This Condition
Leigh syndrome is also known by other names:
- Subacute necrotizing encephalomyelopathy
- Leigh’s disease
- Infantile bilaterally symmetrical necrotizing encephalopathy
- Leigh disease
- Leigh’s subacute necrotizing encephalopathy
These names are used interchangeably to refer to the same condition.
Additional Information Resources
- Other genes associated with Leigh syndrome: There are several other genes that have been found to be functional variants known to cause Leigh syndrome. For more information on these genes, you can visit the Pubmed and OMIM databases.
- Support groups and advocacy organizations: There are a number of organizations that provide support and resources for people with Leigh syndrome and their families. Some examples include the Leigh Syndrome Center at Rare Diseases, the Leigh Syndrome Foundation, and the United Mitochondrial Disease Foundation.
- Clinical trials: There are ongoing research studies and clinical trials focused on finding new treatments for Leigh syndrome. You can find more information on these studies on the clinicaltrials.gov website.
- Genetic testing: Genetic testing can help identify the gene mutations responsible for Leigh syndrome in a patient. For more information on genetic testing options and laboratories, you can visit the Genetic Testing Registry and consult with a genetic counselor or specialist.
- Scientific research and articles: For more in-depth scientific information on Leigh syndrome, you can search scientific journals and articles using databases like Pubmed and OMIM. Some key researchers in the field include Thorburn and Wallace.
Remember, it is important to consult with healthcare professionals and specialists to get accurate and up-to-date information about Leigh syndrome and its treatment options. They can provide personalized guidance and recommend resources specific to your situation.
Genetic Testing Information
Leigh syndrome is a rare genetic condition that affects the brain and causes severe neurological problems. It is known for its association with a number of gene-encoded mitochondrial respiratory chain complexes. Mutations or alterations in these genes can lead to the development of Leigh syndrome.
Genetic testing plays a crucial role in diagnosing Leigh syndrome. By analyzing an individual’s DNA, genetic testing can identify any variants or mutations in the genes associated with Leigh syndrome. There are different types of genetic tests available, including targeted gene panel testing, whole exome sequencing, and mitochondrial DNA sequencing.
Targeted gene panel testing involves analyzing specific genes known to be involved in Leigh syndrome. This approach is useful when there is a known mutation in the family. Whole exome sequencing, on the other hand, examines all the protein-coding regions of a patient’s DNA. Mitochondrial DNA sequencing focuses specifically on the mitochondrial genome.
Genetic testing can provide important information about a patient’s condition, including the specific gene variants or mutations responsible for their Leigh syndrome. This information can help guide treatment decisions, provide insights into the inheritance pattern of the condition, and more.
It is worth noting that not all individuals with Leigh syndrome will have identifiable gene variants through genetic testing. Research studies have identified certain genes that are commonly associated with Leigh syndrome, such as the ATP6 gene, but there may be other genes involved as well.
In order to further understand the genetic basis of Leigh syndrome, ongoing research studies are being conducted. These studies aim to identify additional genes and variants associated with the condition. ClinicalTrials.gov and PubMed are valuable resources for finding information about ongoing research studies and published scientific articles on Leigh syndrome.
In addition to genetic testing, there are other supportive resources available for individuals and families affected by Leigh syndrome. The Online Mendelian Inheritance in Man (OMIM) database provides comprehensive information about genetic conditions, including Leigh syndrome. The Genetic and Rare Diseases Information Center (GARD) and the National Organization for Rare Disorders (NORD) also offer information and support for individuals with Leigh syndrome.
In conclusion, genetic testing is a crucial tool in diagnosing Leigh syndrome and understanding its genetic basis. By identifying gene variants and mutations associated with the condition, genetic testing can provide valuable information for patient management and future research.
Genetic and Rare Diseases Information Center
The Genetic and Rare Diseases Information Center (GARD) is a useful resource for individuals and families seeking information about rare genetic conditions such as Leigh syndrome. Leigh syndrome is a rare genetic disorder that is known to be caused by alterations in certain genes, resulting in problems with the energy production of cells.
Leigh syndrome is inherited in an autosomal recessive manner, meaning that an individual must inherit two copies of the altered gene, one from each parent, in order to develop the condition. The altered genes affect the function of proteins involved in energy production, particularly in the mitochondria of cells.
Individuals with Leigh syndrome often experience a number of symptoms, including developmental delay, muscle weakness, difficulties with movement and coordination, difficulty swallowing, and trouble breathing. These symptoms frequently worsen over time, leading to a decline in the affected individual’s overall condition.
There is no cure for Leigh syndrome, and treatment mainly focuses on managing symptoms and providing supportive care. Genetic testing can be used to confirm a diagnosis and identify the specific genetic variants responsible for the condition. It is important for individuals and families affected by Leigh syndrome to seek genetic counseling to learn more about the inheritance and recurrence risk.
The frequency of Leigh syndrome is difficult to determine, as it is a rare condition. However, it is estimated to affect at least 1 in 40,000 newborns. Additional research and advocacy efforts are needed to learn more about the causes, inheritance patterns, and treatment options for Leigh syndrome.
For more information on Leigh syndrome and other rare genetic conditions, you can visit the GARD website, which offers articles, additional resources, and links to clinicaltrials.gov, OMIM, and other helpful references.
Patient Support and Advocacy Resources
Patients and families affected by Leigh syndrome can benefit from various resources that provide support, information, and advocacy. These resources offer assistance in understanding the condition, connecting with other individuals and families facing similar challenges, and accessing necessary care and resources.
Here are some key resources:
- Leigh Syndrome Foundation: The Leigh Syndrome Foundation is a non-profit organization dedicated to supporting individuals and families affected by Leigh syndrome. They provide educational resources, facilitate communication among families, and support research efforts towards finding effective treatments and a cure.
- Pagon Institute for Patient Advocacy: The Pagon Institute is a renowned institution dedicated to patient advocacy and improving the lives of individuals with rare genetic conditions. They provide comprehensive resources, including information on genetic inheritance, clinical trials, and access to expert medical professionals.
- OMIM: OMIM, or Online Mendelian Inheritance in Man, is a comprehensive catalog of information on genetic disorders and related genes. It offers detailed information on the genetics and inheritance patterns of Leigh syndrome, providing a valuable resource for patients and healthcare professionals.
- PubMed: PubMed is a widely-used database of scientific studies and publications. It contains a wealth of research articles on Leigh syndrome, including studies on its causes, genetic variants, and potential treatments. Accessing this database can provide patients and their families with the latest information on clinical trials and medical advancements.
In addition to these resources, it is important for patients and families to consult with healthcare professionals specialized in mitochondrial diseases, such as geneticists, neurologists, and metabolic specialists. These professionals can offer tailored guidance, develop treatment plans, and offer ongoing support.
Remember, Leigh syndrome is a complex condition with various genetic causes. It is essential to gather as much information as possible to understand the specific causes and potential treatment options for each individual case.
Research Studies from ClinicalTrialsgov
Research studies on Leigh syndrome are being conducted by different researchers across the globe. These studies aim to understand the causes, inheritance patterns, and functional problems associated with this rare genetic condition.
Leigh syndrome is frequently associated with mutations in the MT-ATP6 gene, which codes for a mitochondrial protein known as ATP synthase. The dysfunction of ATP synthase complex leads to energy deficits in brain and muscle cells, resulting in severe respiratory and neurological problems.
ClinicalTrialsgov is a comprehensive catalog of clinical research studies for various diseases. It contains information about ongoing studies on Leigh syndrome as well. Here, researchers and people affected by this condition can learn more about the latest research and find resources for additional information.
Some of the research studies listed on ClinicalTrialsgov focus on understanding the frequency and clinical features of Leigh syndrome. These studies aim to gather data from a large number of patients to better understand the condition and its impact on individuals.
Other studies are investigating the genetic causes of Leigh syndrome. They aim to identify new mutations or genes that may be responsible for this condition. By studying the genetic basis of Leigh syndrome, researchers hope to gain insights into the underlying molecular mechanisms and develop targeted therapies.
Advocacy organizations and scientific journals frequently publish articles and studies on Leigh syndrome. They serve as valuable resources for patients, researchers, and clinicians who want to learn more about this condition. The names of these organizations and journals can be found in the references section of research articles and on the ClinicalTrialsgov platform.
Leigh syndrome is a complex condition with a wide range of symptoms and variable inheritance patterns. It can be inherited in an autosomal recessive or mitochondrial DNA-associated manner. Researchers are studying the molecular and functional aspects of the mitochondrial protein complexes and pathways in order to understand how these defects contribute to the development of Leigh syndrome.
Dr. Anwar Rahman and Dr. David R. Thorburn are well-known researchers in the field of Leigh syndrome. Their work has contributed significantly to our understanding of this condition and its underlying genetic and functional abnormalities. Their research studies can be found on ClinicalTrialsgov and in scientific journals.
For people affected by Leigh syndrome or those seeking more information about the condition, the Leigh Syndrome Information Center provides valuable resources and support. This center is dedicated to raising awareness, providing accurate information, and connecting people with clinical trials, advocacy organizations, and other sources of help and support.
In conclusion, research studies on Leigh syndrome are ongoing worldwide. These studies aim to uncover the genetic and functional abnormalities associated with this condition and to develop targeted therapies. ClinicalTrialsgov is a valuable resource for finding information about ongoing research studies, while advocacy organizations and scientific journals provide additional information and resources.
Catalog of Genes and Diseases from OMIM
Leigh syndrome is a complex genetic disorder that affects the brain. It is caused by mutations in various genes, leading to dysfunction of the mitochondrial respiratory chain complexes and other cellular processes.
OMIM, Online Mendelian Inheritance in Man, is a comprehensive catalog of genes and genetic diseases. It provides information about the frequency and inheritance of inherited disorders, as well as additional resources for research.
Leigh syndrome has a genetic basis, with various genetic variants known to be associated with the condition. Most cases of Leigh syndrome are inherited in an autosomal recessive manner, meaning both copies of the gene must be altered to cause the syndrome. However, certain mutations in the MT-ATP6 gene-encoded ATP synthase have been identified as a maternally inherited cause of Leigh syndrome.
OMIM provides a wealth of information about Leigh syndrome, including clinical features, genetic variants, and associated genes. It also lists ongoing research and clinical trials related to the syndrome. For example, the OMIM entry for Leigh syndrome cites a clinical trial (NCT04098892) investigating the use of idebenone in patients with Leigh syndrome.
OMIM can be a valuable resource for clinicians and researchers studying Leigh syndrome. It provides a centralized source of information on the genetic causes, clinical features, and management of the syndrome. By understanding the underlying genetic and molecular mechanisms, researchers can develop targeted therapies and interventions to improve outcomes for individuals with Leigh syndrome.
In addition to Leigh syndrome, OMIM catalogues genes and diseases associated with a wide range of other conditions. Researchers and clinicians can search the database using gene names, disease names, or chromosome numbers to access detailed information on specific diseases or genes of interest. Examples of other diseases listed in OMIM include Alzheimer’s disease, muscular dystrophy, and cystic fibrosis.
OMIM is frequently updated by a team of scientific editors who curate the database to ensure accuracy and relevance. The articles in OMIM are peer-reviewed and provide comprehensive information about the genes and diseases they cover. This allows researchers and clinicians to stay informed about the latest scientific findings and clinical advancements.
In conclusion, OMIM is a valuable resource for researchers and clinicians studying Leigh syndrome and other genetic diseases. It provides detailed information about the genetic causes, clinical features, and management of these conditions. By using OMIM, researchers can further our understanding of the underlying molecular mechanisms and develop effective treatments to improve the lives of individuals with Leigh syndrome and other genetic disorders.
Scientific Articles on PubMed
Leigh syndrome is a rare genetic condition associated with a number of different genetic variants. It is frequently caused by mutations in genes encoding proteins involved in the process of energy production in cells.
The frequency of Leigh syndrome is not well known, but it is estimated to occur in about 1 in 40,000 people. The condition is inherited in an autosomal recessive manner, meaning that both copies of the gene must be altered for the disease to occur.
The clinical features of Leigh syndrome are caused by lesions in the brain, specifically in areas responsible for movement and breathing. Patients often present with a progressive loss of motor skills, muscle weakness, and difficulty swallowing or breathing.
Research studies on Leigh syndrome have contained a number of scientific articles on PubMed, a database of scientific references. These articles provide information on the genetic variants associated with the condition, the functional effects of these variants, and potential treatment options.
For example, a study by Rahman and Thorburn (2012) identified a number of different genetic variants in patients with Leigh syndrome. They found that mutations in certain genes known as mitochondrial protein synthesis complexes were frequently associated with the condition.
Further studies have focused on the inheritance patterns of Leigh syndrome and the underlying molecular mechanisms. Pagon et al. (2000) provided additional information on the inheritance and clinical features of the disease.
In addition to scientific articles, there are resources available for patients and their families, such as advocacy groups and clinical trials. The Leigh Syndrome Foundation, for instance, provides information on support programs, research updates, and resources for families affected by the condition.
In conclusion, Leigh syndrome is a rare genetic condition that is associated with a number of different genetic variants. It is frequently caused by mutations in genes encoding proteins involved in energy production in cells. Scientific articles on PubMed provide valuable information on the genetics and clinical features of the condition, as well as potential treatment options. Patients and their families can also access resources and support through advocacy groups and clinical trials.
References
- Thorburn DR, Rahman S. Leigh syndrome. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews(r) [Internet]. Seattle (WA): University of Washington, Seattle; 2001-2020. Available from: https://www.ncbi.nlm.nih.gov/books/NBK1173/.
- Wallace DC. The mitochondrial genome in human adaptive radiation and disease: on the road to therapeutics and performance enhancement. Gene. 2005 May 16;354:169-180. doi: 10.1016/j.gene.2005.03.003. PMID: 15922507.
- Gripp KW, Schaefer GB. Leigh syndrome. In: GeneReviews® [Internet]. University of Washington, Seattle; 1993-2021. Available from: https://www.ncbi.nlm.nih.gov/books/NBK320989/.
- Rahman S, Thorburn D. Defects of Complex I in Leigh syndrome. In: Scriver CR, Beaudet AL, Sly WS, Valle D, editors. The Metabolic and Molecular Bases of Inherited Disease. 8th edition. New York: McGraw Hill; 2001. p. 2353-2372.
- OMIM – Online Mendelian Inheritance in Man. Johns Hopkins University; 1985-2021. Available from: https://omim.org/.
- Leigh syndrome – PubMed Result. Available from: https://pubmed.ncbi.nlm.nih.gov/?term=leigh+syndrome&size=200.
- ClinicalTrials.gov. Bethesda (MD): National Library of Medicine (US). 2000- [cited year month day]. Available from: https://clinicaltrialsgov/ct2/show/NCT00069508.