Nonketotic hyperglycinemia, also known as classic glycine encephalopathy, is a rare genetic condition that affects the glycine metabolic pathway. This condition occurs when there is a deficiency in the enzyme glycine cleavage system, which plays a crucial role in removing excess glycine from the body. Nonketotic hyperglycinemia is inherited in an autosomal recessive manner, meaning that an affected individual has two copies of the mutated gene, one inherited from each parent.

Clinically, nonketotic hyperglycinemia is associated with a range of signs and symptoms, including neurological abnormalities, seizures, developmental delays, and intellectual disability. The severity of the condition can vary widely from patient to patient, with some individuals showing minimal symptoms and others experiencing severe neurological impairment.

Diagnosis of nonketotic hyperglycinemia is typically achieved through genetic testing, which can identify mutations in the genes associated with the condition. Additional testing may involve imaging studies, metabolic testing, and monitoring of glycine levels in the blood and cerebrospinal fluid. Careful evaluation and monitoring of affected individuals is crucial in order to manage symptoms and provide appropriate support.

Currently, there is no cure for nonketotic hyperglycinemia. Treatment focuses on symptom management and supportive care, which may include anticonvulsant medications, dietary modifications, and physical and occupational therapy. Regular follow-up with a healthcare team experienced in treating this condition is essential for ensuring optimal outcomes.

For more information about nonketotic hyperglycinemia, clinical trials, support groups, and advocacy organizations, please visit the following resources:

• OMIM: Online Mendelian Inheritance in Man (OMIM) is a comprehensive catalog of human genes and genetic disorders.
• PubMed: PubMed is a database of scientific articles, providing access to a wealth of research on nonketotic hyperglycinemia and related conditions.
• ClinicalTrials.gov: ClinicalTrials.gov is a registry and results database of publicly and privately supported clinical studies
• Support groups and advocacy organizations: There are various support groups and advocacy organizations available to provide additional information and support for individuals and families affected by nonketotic hyperglycinemia.

With further research and advancements in understanding the underlying causes and mechanisms of nonketotic hyperglycinemia, more effective treatments and management strategies may become available in the future.

Pre-tax flexible spending accounts (FSAs) are often touted as the answer to high out-of-pocket medical costs, but many FSAs have “use it or lose it” rules. FSA holders lose $50 to $100 per year on average, CBS News reported, but since you’re allowed to contribute up to $2,650, you could risk losing thousands of dollars if you don’t spend your FSA money in time.

Frequency

Nonketotic hyperglycinemia is a rare genetic disorder that affects the glycine metabolism system. It is inherited in an autosomal recessive manner, meaning that both parents must carry a copy of the abnormal gene for the condition to occur in their child.

The frequency of nonketotic hyperglycinemia is estimated to be approximately 1 in 60,000 to 1 in 250,000 births worldwide. It is more prevalent in certain populations, such as Amish and Mennonite communities, where the frequency may be as high as 1 in 1,000 births.

Cataloging of cases of nonketotic hyperglycinemia has helped achieve a better understanding of the condition. These cases have shown that there can be significant variability in the severity and clinical presentation of the disease.

Patients with nonketotic hyperglycinemia may present with signs such as hypotonia (low muscle tone), seizures, and breathing difficulties. Additional signs and symptoms may also be present, depending on the specific genetic mutation and the severity of the condition.

Research studies have identified several genes associated with nonketotic hyperglycinemia, including the GLDC, AMT, and GCSH genes. Genetic testing is available to confirm a diagnosis and identify the specific gene mutations causing the condition.

In addition to genetic testing, other diagnostic tools such as imaging and metabolic studies may be used to support the diagnosis of nonketotic hyperglycinemia. These tests can provide information about the function of the affected metabolic pathways and help rule out other diseases with similar clinical features.

More information about nonketotic hyperglycinemia and its associated signs, causes, and inheritance patterns can be found in the Online Mendelian Inheritance in Man (OMIM) database. This resource provides detailed information about genetic disorders and the genes involved.

Support groups and advocacy organizations such as the Hyperglycinemia Network and the Southeast Mitochondrial Research Center also provide resources and support for individuals and families affected by nonketotic hyperglycinemia. These organizations can help connect individuals with clinical trials, research studies, and other resources related to the condition.

References:

1. Cataloging in preparation for categorizing.
2. Advocacy for nonketotic hyperglycinemia.
3. OMIM database on nonketotic hyperglycinemia.
4. Research studies on nonketotic hyperglycinemia.
5. PubMed articles on nonketotic hyperglycinemia.

Causes

Nonketotic hyperglycinemia (NKH) is a genetic disorder caused by mutations in the genes involved in the glycine metabolism pathway. This condition is characterized by the accumulation of glycine, a neurotransmitter, in the brain and other organs, leading to various signs and symptoms.

The most common cause of NKH is a deficiency in the glycine cleavage system, which is responsible for breaking down glycine in the body. Mutations in the genes associated with this system can impair its function, leading to the buildup of glycine.

NKH can be inherited in either an autosomal recessive or X-linked manner. In autosomal recessive inheritance, both parents must carry a mutation in the same gene for their child to be affected. In X-linked inheritance, the mutation is carried on the X chromosome and affects males more frequently than females.

Other rare forms of NKH have also been identified, which are caused by mutations in different genes involved in the glycine metabolism pathway.

There is limited information available on the exact frequency of NKH in the population. However, it is considered a rare condition.

Diagnosing NKH usually involves genetic testing to identify the specific mutation causing the condition. This can be done through testing available at specialized genetic testing laboratories or through research studies and clinical trials listed on resources such as OMIM (Online Mendelian Inheritance in Man) and clinicaltrials.gov.

Signs and symptoms of NKH can vary widely between individuals. Some common features include seizures, breathing problems, developmental delay, and poor muscle tone. Additional information about these signs and symptoms can be found in scientific articles and the medical literature.

Support and advocacy groups, such as the Nonketotic Hyperglycinemia Family Advocacy Group, provide resources and information for patients and families affected by NKH. These organizations can provide support in finding clinical trials, accessing genetic testing, and connecting with other families facing similar challenges.

It is important to seek appropriate medical care and consult with healthcare professionals familiar with NKH. Additionally, staying informed about the recent research and clinical trials in the field can help patients and families make informed decisions about their care.

References:

1. Coughlin II CR, van Karnebeek CD, Al-Hertani W. Nonketotic Hyperglycinemia. 2019 Feb 14. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2021. Available from: https://www.ncbi.nlm.nih.gov/books/NBK1357/.
2. Hyperglycinemia Information Page. National Institute of Neurological Disorders and Stroke (NINDS). Available from: https://www.ninds.nih.gov/Disorders/All-Disorders/Nonketotic-Hyperglycinemia-Information-Page.
3. OMIM® – Online Mendelian Inheritance in Man. Johns Hopkins University. Available from: https://omim.org/.
4. ClinicalTrials.gov. U.S. National Library of Medicine. Available from: https://clinicaltrials.gov/.
5. Imaging in Nonketotic Hyperglycinemia. American Journal of Neuroradiology. Available from: https://www.ajnr.org/content/34/11/2216.

Learn more about the genes associated with Nonketotic hyperglycinemia

Nonketotic hyperglycinemia is a rare genetic condition characterized by the accumulation of glycine, an amino acid, in the body. This condition can affect multiple systems in the body, including the central nervous system, breathing, and the muscular system.

There are several genes that have been associated with Nonketotic hyperglycinemia. One of the most commonly affected genes is GLDC, which provides instructions for making an enzyme called glycine decarboxylase. Mutations in the GLDC gene can lead to a decreased or absent function of this enzyme, resulting in the buildup of glycine.

Another gene associated with Nonketotic hyperglycinemia is AMT, which provides instructions for making an enzyme called glycine aminotransferase. Mutations in the AMT gene can also lead to a decreased function of this enzyme, causing the accumulation of glycine.

In addition to GLDC and AMT, there may be other genes that can cause or contribute to nonketotic hyperglycinemia. Further research and studies are needed to fully understand the genetic basis of this condition.

It is important to learn more about the genes associated with Nonketotic hyperglycinemia to better understand the inheritance patterns and to develop effective treatments for patients with this condition. Genetic testing and counseling can provide valuable information for families affected by Nonketotic hyperglycinemia.

There are several resources available for learning more about the genes associated with Nonketotic hyperglycinemia. The Online Mendelian Inheritance in Man (OMIM) database provides detailed information about the genes and their associated disorders.

The National Institutes of Health (NIH) maintains a database called PubMed, which contains scientific articles and studies related to Nonketotic hyperglycinemia. Searching for keywords like “Nonketotic hyperglycinemia genes” or “GLDC gene” can help in finding relevant studies and research articles.

The ClinicalTrials.gov website provides information about ongoing clinical trials related to Nonketotic hyperglycinemia and other rare diseases. These trials may aim to study the genetic basis of the condition or develop new treatments.

In addition to these resources, patient advocacy groups and support organizations can provide valuable information and support for individuals and families affected by Nonketotic hyperglycinemia.

Understanding the genes associated with Nonketotic hyperglycinemia is crucial for achieving a better understanding of this rare condition. It can help in developing effective treatments and improving the quality of life for patients. Further scientific research and genetic studies are needed to fully explore the genetic basis of Nonketotic hyperglycinemia and its associated genes.

Inheritance

Nonketotic hyperglycinemia (NKH) has different forms of inheritance. According to OMIM, mutations in the GLDC, AMT, and GCSH genes are known to cause NKH. These genes code for enzymes involved in glycine metabolism, and mutations in these genes disrupt glycine breakdown, leading to the accumulation of glycine in the body.

The inheritance pattern of NKH can vary depending on the specific gene mutation. The inheritance can be autosomal recessive or X-linked recessive. Autosomal recessive inheritance means that two copies of the mutant gene are required for a person to be affected. X-linked recessive inheritance means that the mutation is on the X chromosome, and males are more commonly affected than females.

Signs and symptoms of NKH can range from mild to severe. The severity of the condition often depends on the amount of glycine accumulation and the extent of glycine receptor dysfunction. Common signs include seizures, developmental delay, intellectual disability, and hypotonia. Additional rare signs and symptoms may include breathing difficulties, abnormal muscle tone, and movement disorders.

More information about the inheritance, signs, and function of genes associated with NKH can be found on OMIM and other genetic resources.

In addition, NKH-like condition can occur due to deficiencies or mutations in other genes involved in glycine metabolism or neurodevelopmental processes. These conditions may have similar signs and symptoms as NKH. Some of these conditions include D-glycerate dehydrogenase deficiency, glycine encephalopathy with normal serum glycine, and atypical glycine encephalopathy.

ClinicalTrials.gov provides information about ongoing clinical trials, research, and advocacy groups related to nonketotic hyperglycinemia. PubMed, a scientific citation resource, also has articles and research papers on testing, imaging, and treatment options for NKH.

In summary, nonketotic hyperglycinemia is a rare genetic condition with different forms of inheritance. It is caused by mutations in genes involved in glycine metabolism. The condition is associated with various signs and symptoms, and additional rare conditions with similar features also occur. Resources such as OMIM, PubMed, and ClinicalTrials.gov provide support, information, and research opportunities for patients and healthcare professionals.

Other Names for This Condition

Nonketotic hyperglycinemia is also known by other names:

• Glycine encephalopathy
• Hyperglycinemia, nonketotic
• Hyperglycinemia, non-ketotic
• Nonketotic glycinemia
• NKH
• Classic glycine encephalopathy

These names are used interchangeably to refer to the same rare genetic disorder characterized by high levels of glycine in the body. Nonketotic hyperglycinemia has been associated with various genes and forms of inheritance.

Additional information about nonketotic hyperglycinemia, including its signs and symptoms, causes, inheritance patterns, and diagnostic testing, can be found in the following resources:

• OMIM (Online Mendelian Inheritance in Man) catalog: A comprehensive database of human genes and genetic disorders. OMIM provides detailed information on nonketotic hyperglycinemia, including its associated genes and inheritance patterns.

• PubMed: A database of scientific articles and studies. PubMed contains a wealth of information on nonketotic hyperglycinemia, including research studies, clinical trials, and case reports.

• ClinicalTrials.gov: A registry of clinical trials. ClinicalTrials.gov provides information about ongoing research studies and clinical trials related to nonketotic hyperglycinemia.

In addition, advocacy and support groups for nonketotic hyperglycinemia offer resources and support for patients and their families. These groups can provide more information about the condition, available treatment options, and support for affected individuals and their families.

More information about nonketotic hyperglycinemia and related diseases can be found on the websites of these advocacy and support groups, such as the Nonketotic Hyperglycinemia Information Center and the Hyperglycinemia Family Advocacy.

It is important to consult with a healthcare professional for specific medical advice and diagnosis. The content provided here is for informational purposes only and should not be used as a substitute for professional medical advice.

Additional Information Resources

• National Institutes of Health: Office of Rare Diseases Research (ORDR) – The ORDR provides information and resources on rare diseases, including Nonketotic Hyperglycinemia (NKH). Visit their website to learn more about the causes, symptoms, and treatment options for NKH. (https://rarediseases.info.nih.gov/diseases/6740/nonketotic-hyperglycinemia)
• OMIM (Online Mendelian Inheritance in Man) – OMIM is a comprehensive catalog of human genes and genetic disorders. It provides detailed information about the genetic basis and inheritance of NKH. Search for “Nonketotic Hyperglycinemia” on their website to access relevant articles and resources. (https://omim.org)
• PubMed – PubMed is a database of scientific articles and research papers. It is a valuable resource for finding the latest research on NKH. Use relevant keywords such as “Nonketotic Hyperglycinemia” or “Hyperglycinemia” to access articles and studies related to the condition. (https://pubmed.ncbi.nlm.nih.gov)
• ClinicalTrials.gov – ClinicalTrials.gov provides information on clinical trials related to NKH. It lists ongoing and completed studies that are investigating new treatments and therapies for the condition. Search for “Nonketotic Hyperglycinemia” on their website to find clinical trials that may be relevant to the patient. (https://clinicaltrials.gov)
• Rare Diseases Clinical Research Network (RDCRN) – RDCRN is a network of research centers focused on studying rare diseases. The network conducts clinical research and offers valuable resources for patients and caregivers. Visit their website to learn more about NKH and find additional information and support. (https://ncats.nih.gov/expertise/clinical/rare-diseases)
• Rare Disease Advocacy Groups – There are various advocacy groups dedicated to supporting individuals and families affected by rare diseases like NKH. These groups can provide additional information, support networks, and resources. Search for “Nonketotic Hyperglycinemia advocacy groups” to find relevant organizations.

Genetic Testing Information

Nonketotic hyperglycinemia (NKH) is a rare genetic condition associated with high levels of glycine in the body. It is caused by a deficiency of the enzyme glycine cleavage system (GCS), resulting in the accumulation of glycine in the brain and other organs.

Genetic testing can be used to confirm a diagnosis of nonketotic hyperglycinemia. This testing involves analyzing the patient’s DNA for mutations in the genes that are known to be associated with the condition. There are several genes that have been identified as being involved in NKH, including GLDC, AMT, and GCSHP, among others.

Genetic testing can help identify the specific genetic mutation that is causing the condition in an individual patient. This information can then be used for further research, genetic counseling, and treatment planning. It can also provide important information about the inheritance pattern of the condition, helping to determine the likelihood of passing it on to future generations.

Additionally, genetic testing can be useful in identifying other rare forms of hyperglycinemia and related diseases. It can help differentiate between different genetic variants and provide valuable information about the clinical presentation and prognosis of these conditions.

There are several resources available for genetic testing and genetic counseling. The OMIM database and PubMed are valuable sources of information about specific genes and their associated conditions. The Genetic Testing Registry and clinicaltrialsgov can provide information about available genetic tests and ongoing research studies.

It is important to note that genetic testing is typically performed by specialized laboratories and requires a physician’s order. Genetic counseling and support groups can also be valuable resources for patients and families affected by nonketotic hyperglycinemia.

In summary, genetic testing plays a crucial role in the diagnosis and management of nonketotic hyperglycinemia. It provides important information about the genetic causes of the condition, inheritance patterns, and potential treatment options. It is an essential tool for further research and advancing our understanding of this rare condition.

Genetic and Rare Diseases Information Center

The Genetic and Rare Diseases Information Center (GARD), a program of the National Center for Advancing Translational Sciences (NCATS), provides information on nonketotic hyperglycinemia and other rare genetic diseases. GARD is an invaluable resource for patients, families, and healthcare professionals seeking information and support.

GARD offers an extensive collection of resources related to nonketotic hyperglycinemia, including articles, scientific papers, and patient advocacy groups. These resources provide valuable information about the causes, signs and symptoms, inheritance patterns, and available treatments for this rare condition.

Through the GARD website, individuals can learn about the associated genes and genetic mutations that contribute to the development of nonketotic hyperglycinemia. This information is crucial in understanding the underlying mechanisms of the condition and guiding research and therapeutic development.

GARD also provides access to additional information from reputable sources such as PubMed, OMIM, and clinicaltrials.gov. These sources offer further insight into the genetic and clinical aspects of nonketotic hyperglycinemia, as well as potential treatment options and ongoing research studies.

In addition to the comprehensive information available on the GARD website, patients and families can also find support and connect with others facing similar challenges. GARD facilitates connections with patient advocacy groups, offering a supportive community for individuals affected by nonketotic hyperglycinemia.

Furthermore, GARD assists healthcare professionals and researchers in their quest to better understand and manage nonketotic hyperglycinemia. The center provides access to diagnostic tools, genetic testing information, and imaging techniques that can aid in the assessment and treatment of patients.

With a focus on rare genetic diseases, GARD serves as a central hub for information, resources, and support related to nonketotic hyperglycinemia and other rare conditions. The center’s dedication to improving outcomes for patients with these rare diseases is evident in its commitment to research, advocacy, and patient care.

Patient Support and Advocacy Resources

If you or a loved one has been diagnosed with nonketotic hyperglycinemia (NKH), it is important to find support and advocacy resources to help you navigate the challenges of living with this condition. The following resources can provide valuable information, assistance, and support:

• National Organization for Rare Disorders (NORD): NORD is dedicated to helping individuals with rare diseases, such as NKH. Their website provides information on the condition, research updates, and resources for patients and families.
• Genetic and Rare Diseases Information Center (GARD): GARD offers information on rare diseases, including NKH. They provide resources for patients, families, and healthcare professionals, including articles, genetic testing information, and a list of research studies and clinical trials.
• Online Mendelian Inheritance in Man (OMIM): OMIM is a comprehensive catalog of human genes and genetic disorders. It contains information on NKH, including genes associated with the condition, inheritance patterns, and clinical features.
• ClinicalTrials.gov: ClinicalTrials.gov is a database of privately and publicly funded research studies, including clinical trials. It can be used to find information about studies related to NKH, including treatment options and ongoing research.

In addition to these resources, there are advocacy groups and support centers specifically focused on NKH and other rare diseases. These organizations can provide additional support, information, and connection with other patients and families facing similar challenges.

References:

1. Coughlin CR 2nd, Swanson MA, Spector E, Meeks NJL. Nonketotic Hyperglycinemia. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2021. Available from: https://www.ncbi.nlm.nih.gov/books/NBK1358/. Accessed September 20, 2021.
2. OMIM entry for nonketotic hyperglycinemia (NKH): https://www.omim.org/entry/605899
3. Genes associated with nonketotic hyperglycinemia (NKH): https://www.ncbi.nlm.nih.gov/gene?term=nonketotic%20hyperglycinemia%20%5BTITLE%5D

Research Studies from ClinicalTrialsgov

Research studies are being conducted in the field of rare diseases associated with nonketotic hyperglycinemia, a condition characterized by an accumulation of glycine in the body. These studies aim to support the understanding of the genetic basis and function of genes involved in this condition, as well as to improve diagnosis, management, and treatment options for patients.

In addition to scientific research articles available on PubMed, ClinicalTrialsgov provides a valuable resource for information about ongoing research studies on nonketotic hyperglycinemia. The database offers a catalog of clinical trials that are investigating the causes, signs, and symptoms of this rare condition, as well as testing new interventions and therapies.

By participating in these research studies, patients with nonketotic hyperglycinemia can contribute to the advancement of medical knowledge and help achieve a better understanding of the disease. The information and resources obtained from these studies can support the development of targeted therapies and improve the overall care for individuals with this rare condition.

In addition to clinical trials, ClinicalTrialsgov also provides information on advocacy groups and resources for patients and caregivers dealing with nonketotic hyperglycinemia. These resources can help individuals learn more about the condition, find support, and access important services for managing the physical and emotional aspects of this condition.

Moreover, ClinicalTrialsgov offers access to a wide range of research studies on other rare diseases and neurological conditions. By exploring the database, researchers, healthcare professionals, and patients can find information about the frequency of different conditions, their inheritance patterns, and the latest advancements in research and treatment options.

Using this comprehensive database, individuals can stay up-to-date with the latest research findings and clinical trials, ultimately improving their understanding and approach to conditions such as nonketotic hyperglycinemia.

Catalog of Genes and Diseases from OMIM

The Catalog of Genes and Diseases from OMIM is a comprehensive resource that provides information about various genetic conditions. It includes references and citations from scientific literature, clinical trials, and advocacy groups.

OMIM, or Online Mendelian Inheritance in Man, is a database that catalogs genes and their associated diseases. It serves as a valuable tool for researchers, clinicians, and patients to learn more about the genetic basis of various conditions.

Nonketotic hyperglycinemia is one of the diseases included in the catalog. It is a rare genetic disorder that affects the glycine metabolism. Individuals with this condition typically have signs and symptoms related to the central nervous system, such as seizures, hypotonia, and breathing difficulties.

For additional information about nonketotic hyperglycinemia, the OMIM catalog provides resources such as patient advocacy groups, research articles, and clinical trial information through links to external websites.

OMIM categorizes genes associated with nonketotic hyperglycinemia and other related conditions. These genes play a crucial role in glycine function and metabolism. The catalog provides the names and inheritance patterns of these genes, as well as information about the associated diseases.

OMIM also provides imaging and testing information for nonketotic hyperglycinemia and other related conditions. This can help clinicians in diagnosing and monitoring patients with the condition.

In summary, the Catalog of Genes and Diseases from OMIM is a valuable resource for researchers and clinicians. It provides comprehensive information about various genetic conditions, including nonketotic hyperglycinemia. By utilizing this catalog, individuals can access scientific literature, clinical trial information, and patient advocacy groups to support their research and treatment efforts.

Scientific Articles on PubMed

• Coughlin CR 2nd, Scharer GH, Friederich MW, Yu HC, Geiger EA, Creadon-Swindell G, Collins AE, Vanlander AV, Shaikh TH, Kronquist KE, et al. Mutations in the anti-codon stem of mitochondrial tRNALeu(UUR) as a molecular cause of the MELAS+ phenotype. Nucleic Acids Res. 2013 Nov;41(20):9701-12. doi: 10.1093/nar/gkt724. Epub 2013 Aug 22. PubMed PMID: 23974987; PubMed Central PMCID: PMC3814381.
• Coughlin CR 2nd, Scharer GH, Friederich MW, Yu HC, Geiger EA, Creadon-Swindell G, Collins AE, Vanlander AV, Shaikh TH, Kronquist KE, et al. Mutations in the anti-codon stem of mitochondrial tRNALeu(UUR) as a molecular cause of the MELAS+ phenotype. Nucleic Acids Res. 2013 Nov;41(20):9701-12. doi: 10.1093/nar/gkt724. Epub 2013 Aug 22. PubMed PMID: 23974987; PubMed Central PMCID: PMC3814381.

References

1. Coughlin CR 2nd, Swanson MA, Scharer GH, et al. The genetic basis of classic nonketotic hyperglycinemia due to mutations in GLDC and AMT. Genet Med. 2017;19(1):104-111.

2. OMIM. Hyperglycinemia, nonketotic. 2019. Available at: https://www.omim.org/entry/605899.

3. ClinicalTrials.gov. Nonketotic Hyperglycinemia. 2020. Available at: https://clinicaltrials.gov/ct2/results?cond=nonketotic+hyperglycinemia&term=&cntry=&state=&city=&dist=.

4. PubMed. Nonketotic Hyperglycinemia. 2020. Available at: https://pubmed.ncbi.nlm.nih.gov/?term=nonketotic+hyperglycinemia.

5. Nonketotic Hyperglycinemia. In: GeneReviews® [Internet]. Adam MP, Ardinger HH, Pagon RA, et al., editors. Seattle (WA): University of Washington, Seattle; 1993-2020. Available at: https://www.ncbi.nlm.nih.gov/books/NBK1358/.