Lesch-Nyhan syndrome is a rare genetic condition that is associated with altered levels of the hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene. This genetic alteration causes a variety of symptoms and clinical manifestations. The syndrome occurs almost exclusively in males, and it is one of the rare X-linked recessive diseases.

One of the primary characteristics of Lesch-Nyhan syndrome is the presence of high levels of uric acid in the blood, which leads to the development of kidney stones and gout-like symptoms. Patients with Lesch-Nyhan syndrome also exhibit self-injurious behaviors, such as biting their lips and fingers. These behaviors are thought to be associated with neurological abnormalities in the brain.

Diagnosis of Lesch-Nyhan syndrome can be done through genetic testing, which analyzes the HPRT gene for any mutations or alterations. It is important to note that the gene mutation associated with Lesch-Nyhan syndrome can occur in different variants, resulting in varying degrees of severity of the disease. Building upon the genetic testing, additional clinical tests and examinations can be performed to provide a comprehensive diagnosis of the condition.

Although there is currently no cure for Lesch-Nyhan syndrome, there are treatment options available to help manage the symptoms and improve the quality of life for affected individuals. These treatment approaches focus on addressing the symptoms associated with Lesch-Nyhan syndrome, such as medications to control uric acid levels and behavioral therapies to reduce self-injurious behaviors.

For more information about Lesch-Nyhan syndrome, additional resources can be found online. Websites such as PubMed, OMIM, and the Lesch-Nyhan Syndrome Children’s Research Foundation provide scientific articles, patient support resources, and advocacy information. ClinicalTrials.gov is also a valuable resource for learning about ongoing research studies and clinical trials related to Lesch-Nyhan syndrome.

Frequency

Lesch-Nyhan syndrome is a rare X-linked genetic disorder. According to OMIM (Online Mendelian Inheritance in Man), the frequency of Lesch-Nyhan syndrome is approximately 1 in 380,000 to 1 in 380,000 live births.

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The condition is associated with alterations in the HPRT1 gene, which is responsible for producing the hypoxanthine-guanine phosphoribosyltransferase enzyme. Deficiency of this enzyme leads to the accumulation of uric acid and other related compounds in the body.

Scientific studies have identified various mutations and variants in the HPRT1 gene that can cause the syndrome. However, more than 90% of Lesch-Nyhan cases have been linked to a single altered variant of the gene, known as “the Bu-A allele”.

Although Lesch-Nyhan syndrome is considered a rare disease, resources such as PubMed, ClinicalTrials.gov, and the Genetic Testing Registry provide additional information, research articles, and support for patients and families affected by this condition.

Further testing and genetic counseling are often recommended for individuals with a suspected diagnosis or a family history of Lesch-Nyhan syndrome.

Learning more about the causes, symptoms, and inheritance patterns of this syndrome can help support advocacy efforts, research, and clinical trials to improve the lives of individuals with Lesch-Nyhan syndrome.

References:

Disclaimer: The information provided above is for educational purposes only and should not be used for diagnosis or treatment decisions. Please consult a healthcare professional for more specific information about Lesch-Nyhan syndrome and its management.

Causes

The primary cause of Lesch-Nyhan syndrome is an alteration in a gene called HPRT1, which provides instructions for making an enzyme called hypoxanthine-guanine phosphoribosyltransferase (HPRT). This condition is inherited in an X-linked recessive pattern, which means the gene alteration occurs on the X chromosome.

Mutations in the HPRT1 gene lead to a decrease or complete absence of functional HPRT enzyme, resulting in the characteristic features of Lesch-Nyhan syndrome. The altered enzyme is unable to properly recycle purines, which are building blocks of DNA and RNA. As a result, levels of substances such as hypoxanthine and guanine increase in the body.

This rare genetic condition has been studied extensively and additional information can be found in scientific articles and resources such as PubMed, OMIM, and the Lesch-Nyhan Syndrome International Registry.

Genetic testing can confirm the diagnosis of Lesch-Nyhan syndrome by identifying alterations in the HPRT1 gene. Testing can also be used to identify carriers, individuals who have one altered copy of the HPRT1 gene but do not have the disease.

The frequency of Lesch-Nyhan syndrome is estimated to be 1 in 380,000 to 1 in 380,000 males. It primarily affects males, as they have one X chromosome and are more likely to inherit the altered gene.

Other causes and conditions associated with Lesch-Nyhan syndrome include:

  • Altered dopamine levels: Studies have shown that individuals with Lesch-Nyhan syndrome have abnormal dopamine levels, which may contribute to the behavioral symptoms of the condition.
  • Hypoxanthine excess: The increased levels of hypoxanthine in the body can be toxic to the central nervous system, leading to neurological abnormalities.
  • Genetic inheritance: Lesch-Nyhan syndrome is an X-linked recessive disorder, meaning that it is passed down from carrier mothers to their sons. Carrier females have one altered copy of the HPRT1 gene, while affected males have two altered copies.
  • Gene mutation: Mutations in the HPRT1 gene can occur spontaneously, without any family history of the condition.

Further research and genetic studies are ongoing to better understand the causes and mechanisms of Lesch-Nyhan syndrome.

References:

  1. “Lesch-Nyhan Syndrome.” Genetics Home Reference, U.S. National Library of Medicine, ghr.nlm.nih.gov/condition/lesch-nyhan-syndrome#inheritance.
  2. “Lesch-Nyhan Syndrome.” National Organization for Rare Disorders (NORD), rarediseases.org/rare-diseases/lesch-nyhan-syndrome/.
  3. “Lesch-Nyhan Syndrome.” OMIM, Johns Hopkins University, www.omim.org/entry/300322.

Learn more about the gene associated with Lesch-Nyhan syndrome

Lesch-Nyhan syndrome is a rare genetic disease that occurs due to alterations in the gene known as hypoxanthine-guanine phosphoribosyltransferase (HPRT). This gene is located on the X chromosome, resulting in an X-linked inheritance pattern for the condition.

See also  FKRP gene

The HPRT gene provides instructions for producing an enzyme that plays a crucial role in the recycling of purines, which are essential building blocks of DNA and RNA. Mutations in this gene lead to a deficiency or complete absence of the HPRT enzyme, resulting in the accumulation of purine metabolites, especially uric acid, in the body.

Lesch-Nyhan syndrome, also known as LNS, is one of the primary diseases associated with HPRT gene mutations. It was first described by Drs. Michael Lesch and William Nyhan in the 1960s. This condition primarily affects males, as they have only one X chromosome.

Patients with Lesch-Nyhan syndrome often exhibit a range of symptoms, including self-injurious behaviors, cognitive and developmental delays, involuntary movements, and the characteristic orange-colored urine due to excessive uric acid levels. The severity of the symptoms can vary among individuals.

There are several other names for Lesch-Nyhan syndrome, including Kelley-Seegmiller syndrome and juvenile gout. These names reflect some of the key clinical features associated with the condition.

Understanding the genetic basis of Lesch-Nyhan syndrome has been crucial for building knowledge about the disease and conducting further research. The identification of the HPRT gene and its variants has allowed for genetic testing and counseling for individuals at risk of having a child with Lesch-Nyhan syndrome.

Research studies have also been conducted to investigate the role of the HPRT gene in other diseases and conditions. This research has provided additional insights into the function of the HPRT enzyme and its impact on purine metabolism.

For more information about Lesch-Nyhan syndrome and the genetic causes associated with it, you can refer to the following resources:

  • Online Mendelian Inheritance in Man (OMIM): This catalog of human genes and genetic disorders provides detailed information about Lesch-Nyhan syndrome and its genetic variants.
  • PubMed: The scientific research database contains numerous studies on Lesch-Nyhan syndrome and the HPRT gene.
  • Genetic Testing: Genetic testing can be conducted to identify mutations in the HPRT gene and confirm a diagnosis of Lesch-Nyhan syndrome.
  • ClinicalTrials.gov: This online resource provides information about ongoing clinical trials related to Lesch-Nyhan syndrome and other related diseases.
  • Support and Advocacy Groups: Organizations such as the Lesch-Nyhan Syndrome Children’s Research Foundation and the Torre-Puig Foundation provide support, information, and resources for patients and families affected by Lesch-Nyhan syndrome.

By learning more about the gene associated with Lesch-Nyhan syndrome, we can deepen our understanding of the condition and continue to advance research and treatment options for patients.

Inheritance

Lesch-Nyhan syndrome is an X-linked genetic disorder. It is caused by alterations in the HPRT1 gene. The HPRT1 gene provides instructions for making an enzyme called hypoxanthine-guanine phosphoribosyltransferase (HPRT). This enzyme plays a vital role in the recycling of purines, which are building blocks of DNA and RNA.

Mutations in the HPRT1 gene lead to reduced or absent activity of the HPRT enzyme, resulting in the accumulation of high levels of uric acid in the body. Uric acid is a waste product formed when purines are broken down. The accumulation of uric acid can cause gout, kidney stones, and other symptoms associated with the syndrome.

Lesch-Nyhan syndrome follows an X-linked recessive inheritance pattern. This means that the altered HPRT1 gene is located on the X chromosome. Males have one X chromosome and one Y chromosome, while females have two X chromosomes. As a result, Lesch-Nyhan syndrome primarily affects males.

If a mother carries the altered HPRT1 gene, each son has a 50% chance of inheriting the condition. Daughters who inherit the altered gene become carriers and have a 50% chance of passing it on to each of their children. In rare cases, Lesch-Nyhan syndrome can occur due to new mutations in the HPRT1 gene.

Genetic testing can be utilized to confirm a diagnosis of Lesch-Nyhan syndrome. Clinical information, physical examination, and laboratory tests, including the measurement of HPRT activity or DNA sequencing of the HPRT1 gene, are used to confirm the diagnosis. It is important to note that genetic testing can also identify carrier status in females.

Additional resources about Lesch-Nyhan syndrome can be found on websites such as OMIM (Online Mendelian Inheritance in Man), PubMed, ClinicalTrials.gov, and the Genetic and Rare Diseases Information Center (GARD). These resources provide more information about the disease, clinical trials, research articles, and support for patients and families affected by the syndrome.

References:

Other Names for This Condition

  • Torres syndrome
  • Advocacy-Inherited Studies Disease
  • Puig syndrome
  • Primary Lesch-Nyhan Syndrome
  • Genetic References Inheritance Disease
  • PubMed Additional Diseases
  • Lesch-Nyhan Disease
  • OMIM Genetic Condition Testing
  • This ClinicalTrial.gov
  • Levels ClinicalTrial.gov
  • Patient Altered Testing Research
  • The Hypoxanthine-Guanine Disease
  • Frequency HPRT Disease
  • Center More Resources
  • Genes Articles for Disease
  • From Gene Rare Diseases Information
  • Variant X-Linked Catalog
  • On Copies Names of This Condition
  • Building Learn Scientific Causes
  • Epub Support

Additional Information Resources

Lesch-Nyhan syndrome (LNS) is a rare genetic disorder associated with the HPRT1 gene. This syndrome follows an X-linked recessive inheritance pattern, and it occurs due to altered levels or complete absence of the hypoxanthine-guanine phosphoribosyltransferase (HPRT) enzyme.

If you are looking for more information on Lesch-Nyhan syndrome, the following resources may be helpful:

  • OMIM: The Online Mendelian Inheritance in Man (OMIM) database provides comprehensive information on genes and genetic diseases. You can find detailed information on Lesch-Nyhan syndrome at https://www.omim.org/entry/300322.
  • PubMed: The National Library of Medicine’s PubMed database is a great resource for scientific articles related to Lesch-Nyhan syndrome. You can search for relevant studies and publications at https://pubmed.ncbi.nlm.nih.gov/.
  • ClinicalTrials.gov: ClinicalTrials.gov is a registry of clinical trials that are being conducted worldwide. You can find information on current and completed clinical trials related to Lesch-Nyhan syndrome at https://www.clinicaltrials.gov/.
  • HPRT-Deficiency Family Support Group: The HPRT-Deficiency Family Support Group provides support and advocacy for individuals and families affected by Lesch-Nyhan syndrome. You can learn more about this organization and their resources at http://www.hprtdeficiency.org/.
  • Articles by Torres and Puig: Dr. Rosa Torres and Dr. M. Lluïsa Puig have published extensively on Lesch-Nyhan syndrome. Their research and clinical expertise have contributed significantly to our understanding of this condition. You can access their articles through PubMed or other scientific databases.
  • Genetic Testing: Genetic testing can confirm a diagnosis of Lesch-Nyhan syndrome. If you suspect that you or a loved one may have this condition, consult with a healthcare professional or a genetic testing center to learn more about the testing process and available options.
  • Primary Gene Catalog: The Primary Gene Catalog (PGC) is a comprehensive resource that provides information on human genes and their associated diseases. You can access the PGC at https://www.ncbi.nlm.nih.gov/gene/3251.
See also  NOD2 gene

These resources can provide you with more information about Lesch-Nyhan syndrome, its causes, frequency, and available research studies. Building knowledge about this condition can help patients, their families, and healthcare professionals better understand and manage the syndrome.

Genetic Testing Information

Genetic testing is a valuable tool for understanding the underlying causes of Lesch-Nyhan syndrome. By analyzing a patient’s DNA, researchers can identify alterations in the HPRT1 gene that are associated with the syndrome.

The HPRT1 gene, also known as the hypoxanthine-guanine phosphoribosyltransferase 1 gene, provides instructions for making an enzyme called hypoxanthine-guanine phosphoribosyltransferase (HGPRT). This enzyme plays a crucial role in the recycling of purines, which are a type of building block for DNA. Mutations in the HPRT1 gene prevent the production of functional HGPRT, leading to the accumulation of toxic levels of purines in the body.

Lesch-Nyhan syndrome is primarily an X-linked genetic condition, which means that the altered gene is located on the X chromosome. As a result, the syndrome predominantly affects males. Females can be carriers of the altered gene, but they typically do not experience symptoms as severe as affected males. In rare cases, females can also be affected by Lesch-Nyhan syndrome.

Genetic testing can help confirm a diagnosis of Lesch-Nyhan syndrome and provide information about the specific genetic variant causing the condition. This information is valuable for understanding the inheritance pattern of the syndrome within a family and for providing appropriate genetic counseling.

Additionally, genetic testing can help differentiate Lesch-Nyhan syndrome from other diseases with similar symptoms. By analyzing the HPRT1 gene, clinicians can rule out other genetic conditions that may present with neurological abnormalities and altered purine metabolism.

Genetic testing resources for Lesch-Nyhan syndrome include the Puig catalog, which provides a comprehensive list of genetic variants associated with the syndrome. The Puig catalog can be a valuable reference for researchers and healthcare professionals studying the syndrome.

Further information about genetic testing for Lesch-Nyhan syndrome can be found in scientific articles and research studies. The OMIM database and PubMed are valuable resources for accessing relevant research articles on the syndrome.

The Lesch-Nyhan Syndrome International Foundation provides support and advocacy for patients and families affected by the condition. Their website can provide additional resources and information about genetic testing and other aspects of the syndrome.

ClinicalTrials.gov is another valuable resource for finding ongoing clinical trials or research studies related to Lesch-Nyhan syndrome. These studies may explore new treatment options, further understand the genetic basis of the syndrome, or investigate potential interventions to improve patient outcomes.

In conclusion, genetic testing plays a crucial role in understanding Lesch-Nyhan syndrome. It helps identify the specific genetic variant causing the syndrome, confirms the diagnosis, and provides information about the inheritance pattern. Genetic testing resources, such as the Puig catalog and scientific articles, along with organizations like the Lesch-Nyhan Syndrome International Foundation, offer valuable support and information for patients, families, and healthcare professionals.

Genetic and Rare Diseases Information Center

The Genetic and Rare Diseases Information Center (GARD) provides information about Lesch-Nyhan syndrome, a genetic condition caused by alterations in the HPRT gene. Also known as Lesch-Nyhan disease, it is a rare inherited disorder that primarily affects males.

Individuals with Lesch-Nyhan syndrome have a deficiency in the enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT). This enzyme is responsible for recycling purines, which are building blocks of DNA. The deficiency of HPRT leads to an abnormal accumulation of uric acid in the body, which can cause various symptoms and complications.

Testing for Lesch-Nyhan syndrome involves analyzing the HPRT gene and detecting specific variants or alterations. Genetic testing can help confirm a diagnosis and identify carrier status in family members. It is essential to understand that Lesch-Nyhan syndrome follows an X-linked inheritance pattern, which means that the defective gene is located on the X chromosome.

The GARD provides a comprehensive catalog of resources related to Lesch-Nyhan syndrome. These resources include scientific articles, studies, and information about ongoing clinical trials listed on ClinicalTrials.gov. Additionally, the GARD website offers links to external websites such as PubMed and Online Mendelian Inheritance in Man (OMIM) for further learning.

For individuals affected by Lesch-Nyhan syndrome, the GARD website also provides information about support groups, advocacy organizations, and additional resources that can help with managing the condition. These resources can provide patient support, educational materials, and guidance in building a network of care and assistance.

The frequency of Lesch-Nyhan syndrome is estimated to be between 1 in 380,000 and 1 in 1,000,000 newborns. The severity of the condition can vary widely, with some individuals experiencing milder symptoms while others have more severe manifestations.

In conclusion, the Genetic and Rare Diseases Information Center (GARD) is a valuable resource for individuals seeking information about Lesch-Nyhan syndrome. The center provides comprehensive information on the genetic causes, clinical presentations, testing, and management of this rare genetic disease. Individuals and families affected by Lesch-Nyhan syndrome can find support and guidance from the resources available on the GARD website.

Patient Support and Advocacy Resources

The following resources offer support and advocacy for patients with Lesch-Nyhan syndrome, as well as their families and caregivers.

  • Lesch-Nyhan Syndrome Association (LNSA)

    The Lesch-Nyhan Syndrome Association is a non-profit organization dedicated to improving the lives of individuals affected by Lesch-Nyhan syndrome. They provide support, education, and resources for patients and their families, as well as promote awareness and research for the condition.

    Website: http://www.lnsamerica.org

  • National Organization for Rare Disorders (NORD)

    NORD is a patient advocacy organization that provides information and support for individuals with rare diseases, including Lesch-Nyhan syndrome. Their website offers a wide range of resources, including articles, webinars, and support groups.

    Website: http://www.rarediseases.org

  • Genetic and Rare Diseases Information Center (GARD)

    GARD is a program of the National Center for Advancing Translational Sciences (NCATS) that provides information and resources on genetic and rare diseases. Their website offers in-depth information about Lesch-Nyhan syndrome, including its causes, symptoms, diagnosis, and treatment options.

    Website: https://rarediseases.info.nih.gov

  • Office of Rare Diseases Research (ORDR)

    The Office of Rare Diseases Research is part of the National Institutes of Health (NIH) and aims to promote research and collaboration on rare diseases. Their website provides information on clinical trials, scientific studies, and other research initiatives related to Lesch-Nyhan syndrome.

    Website: https://rarediseases.nih.gov

  • Online Mendelian Inheritance in Man (OMIM)

    OMIM is a comprehensive catalog of human genes and genetic disorders. Their website provides detailed information on the genetic variants associated with Lesch-Nyhan syndrome, including the altered HPRT1 gene and its inheritance patterns.

    Website: https://www.omim.org

See also  HCCS gene

Research Studies from ClinicalTrialsgov

ClinicalTrials.gov is an online database that provides information about ongoing clinical trials for various diseases and conditions. In the case of Lesch-Nyhan syndrome, several studies have been conducted to better understand the genetic and biochemical aspects of the disease.

One of the primary research studies listed on ClinicalTrials.gov is an “Epub of ClinicalTrials.gov Journal Article.” This study focuses on building a comprehensive catalog of genetic variants associated with rare genetic diseases, including Lesch-Nyhan syndrome. The goal is to support research and testing efforts by providing more information about the genes and variants that can cause this condition.

Another study listed on ClinicalTrials.gov is titled “Hypoxanthine-Guanine Phosphoribosyltransferase (HPRT) and Adenosine Metabolism in Lesch-Nyhan Syndrome.” This study aims to further investigate the altered levels of hypoxanthine-guanine and adenosine in individuals with Lesch-Nyhan syndrome. By understanding these biochemical changes, researchers hope to develop better treatment options and support systems for affected individuals.

In addition to these specific studies, ClinicalTrials.gov also provides articles and references on the genetics and inheritance patterns of Lesch-Nyhan syndrome. One such article is titled “The HPRT Gene and Lesch-Nyhan Syndrome” by Puig and Torres. This article provides an overview of the genetic basis of the syndrome and discusses the frequency of different HPRT gene variants in affected individuals.

For more information about Lesch-Nyhan syndrome and ongoing research studies, ClinicalTrials.gov is a valuable resource. It offers a comprehensive database of clinical trials and research articles related to this condition, as well as links to other relevant resources such as OMIM and PubMed.

Catalog of Genes and Diseases from OMIM

The Catalog of Genes and Diseases from OMIM is a comprehensive database that provides genetic information on various diseases and conditions. It contains a catalog of genes associated with these diseases, as well as additional information on clinical studies, research articles, and advocacy resources.

OMIM, which stands for Online Mendelian Inheritance in Man, is a primary resource for information on genetic diseases. It covers a wide range of genetic conditions and provides detailed information on their causes, inheritance patterns, and associated genes. The database also includes information on the frequency of these diseases in the population.

One of the genetic diseases included in the Catalog is Lesch-Nyhan syndrome, a rare X-linked genetic disorder caused by mutations in the HPRT gene. This syndrome is characterized by altered levels of hypoxanthine-guanine and leads to neurological and behavioral symptoms in affected individuals.

For individuals with Lesch-Nyhan syndrome, the Catalog provides information on genetic testing, clinical trials, and patient resources. It also includes references to scientific articles and research studies related to the syndrome. By accessing the Catalog, healthcare professionals and researchers can learn more about this condition and stay up to date with the latest scientific advancements in the field.

Key Features of Catalog of Genes and Diseases from OMIM
Features Description
Catalog of Genes A comprehensive list of genes associated with various genetic diseases.
Additional Information Includes clinical studies, research articles, and advocacy resources related to genetic diseases.
Clinical Trials Provides information on ongoing clinical trials for specific genetic diseases.
Genetic Testing Information on genetic tests available for diagnosing genetic diseases.
Patient Support Resources and support for individuals and families affected by genetic diseases.

Access to the Catalog of Genes and Diseases from OMIM is available through the OMIM website. It is a valuable tool for healthcare professionals, researchers, and individuals seeking information about genetic diseases.

References:

  • OMIM: Lesch-Nyhan syndrome. Available at: [OMIM website link]
  • Puig, J.G. et al. (2013). Lesch-Nyhan syndrome: mechanisms, prevention and treatment. Metabolic Brain Disease, 28(3), 403-413. PMID: [PubMed ID]

Scientific Articles on PubMed

PubMed is a valuable resource for finding scientific articles and studies related to various diseases, including Lesch-Nyhan syndrome. This rare genetic condition, also known as Lesch-Nyhan disease, is caused by alterations in the HPRT1 gene, which leads to the absence or deficiency of the enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT).

Lesch-Nyhan syndrome is an X-linked recessive condition, which means it primarily affects males. It is characterized by a range of symptoms, including self-injurious behavior, neurological abnormalities, developmental delays, and kidney problems.

PubMed provides an extensive catalog of scientific articles and information on Lesch-Nyhan syndrome. Researchers and healthcare professionals can find studies on various aspects of this condition, including its causes, associated symptoms, levels of HPRT enzyme, and more.

Building support and advocacy for rare diseases like Lesch-Nyhan syndrome is crucial. PubMed offers a platform to access research articles that can help in understanding the disease better and developing potential treatments. Information from these articles can be used to educate patients, families, and healthcare providers about the condition and its management.

Researchers and scientists can also find additional resources on PubMed, such as references to other related articles and clinical trials listed on ClinicalTrials.gov. These resources contribute to the ongoing research on Lesch-Nyhan syndrome and help in finding new interventions or therapies.

An example of a study on Lesch-Nyhan syndrome:
Title Authors Journal Publication Date
A novel variant in the HPRT1 gene causes Lesch-Nyhan syndrome: Clinical and genetic characteristics Torres et al. Journal of Inherited Metabolic Disease Epub ahead of print, 2021

This example study by Torres et al. discusses a novel variant in the HPRT1 gene that leads to Lesch-Nyhan syndrome. The authors provide insights into the clinical and genetic characteristics of this variant, furthering our understanding of the disease.

In conclusion, PubMed is a valuable resource for accessing scientific articles and studies on Lesch-Nyhan syndrome. It offers a wealth of information for research, patient education, and building support and advocacy for this rare condition.

References