Spinal muscular atrophy with lower extremity predominance

Spinal muscular atrophy with lower extremity predominance, also known as SMALED, is a rare genetic condition that primarily affects the lower extremities of the body. This condition is thought to be caused by a mutation in the DYNC1H1 gene, which is responsible for the production of dynein, a protein involved in maintaining the structure and function of muscles.

Articles on this condition can be found in scientific publications such as PubMed, as well as from resources and references provided by organizations and advocacy groups focused on neurology and rare diseases. Patients and their families can learn more about this condition, its causes, and potential treatment options through these sources.

SMALED is inherited in an autosomal dominant manner, meaning that individuals with a mutation in one of their DYNC1H1 genes have a 50% chance of passing the condition on to their children. The frequency of this condition is not well known due to its rarity, but additional information and support can be found through organizations such as the Spinal Muscular Atrophy Research Center and the Muscular Dystrophy Association.

One of the main characteristics of SMALED is the lower extremity predominance, meaning that the weakness and muscle atrophy primarily affects the muscles in the lower part of the body. Genes involved in SMALED are referred to by different names, including lower extremity-predominant SMA and proximal SMA. The specific symptoms and severity of SMALED can vary from person to person, but it is generally considered a childhood-onset condition.

Frequency

Spinal muscular atrophy with lower extremity predominance (SMA-LED) is a rare genetic condition that is characterized by muscle weakness and atrophy, particularly in the lower extremities. It is also known as DYNC1H1-related SMA.

The frequency of SMA-LED is not well established, as it is a rare condition. However, it is thought to be more common than other forms of spinal muscular atrophy. SMA-LED is inherited in an autosomal dominant manner, which means that an affected individual has a 50% chance of passing the condition on to each of their children.

The prevalence of SMA-LED is likely higher than currently reported, as it may be underdiagnosed or misdiagnosed due to its similarity to other neuromuscular disorders. Diagnosis of SMA-LED is typically based on a combination of clinical symptoms, such as muscle weakness and atrophy, and genetic testing to identify mutations in the DYNC1H1 gene.

Additional information about SMA-LED can be found on websites and resources dedicated to spinal muscular atrophy, such as the Spinal Muscular Atrophy Research Team (SMART) and the CureSMA Foundation. These websites provide support and advocacy for individuals with SMA-LED and their families, as well as information on genetic testing and treatment options.

Scientific articles and publications on SMA-LED can be accessed through databases such as PubMed. Some relevant articles include studies on the association of DYNC1H1 mutations with lower extremity-predominant spinal muscular atrophy, as well as articles on other genes and factors that may contribute to the development of the condition.

Overall, while SMA-LED is a rare and relatively understudied condition, more research and resources are becoming available to support individuals and families affected by this unique form of spinal muscular atrophy.

Causes

Spinal muscular atrophy with lower extremity predominance (SMA-LED) is a rare genetic condition that affects the muscles, particularly those in the lower extremities.

This condition is caused by a mutation in the DYNC1H1 gene, which provides instructions for making a protein called dynein cytoplasmic 1 heavy chain 1 (DYNC1H1). The DYNC1H1 protein is involved in the movement of various cellular structures within the body, including the transport of proteins and other substances along nerve cells.

SMA-LED is inherited in an autosomal recessive manner, which means that an affected individual must inherit two copies of the mutated gene – one from each parent. When both parents are carriers of the mutation, each of their children has a 25% chance of inheriting both copies of the gene and developing SMA-LED.

It is thought that the lower extremities are predominantly affected in SMA-LED due to the specific role of DYNC1H1 in maintaining the structure and function of these muscles. Other muscles may also be affected to a lesser degree.

Additional genetic mutations have been associated with similar forms of spinal muscular atrophy, including subtypes referred to as SMALED1 and SMALED2. These subtypes are caused by mutations in genes other than DYNC1H1, such as TRPV4 or BICD2.

For more information about the genetic causes of SMA-LED, you may refer to the Online Mendelian Inheritance in Man (OMIM) database, which catalogues genetic disorders and associated genes.

References:

  1. Baloh, R.H. (2011). Genetic causes of distal hereditary motor neuropathies. Neurology, 77(6), 572-573.
  2. OMIM: Spinal muscular atrophy with lower extremity predominance. (Accessed 2021, November 5).
  3. OMIM: Spinal muscular atrophy with lower extremity predominance 1. (Accessed 2021, November 5).
  4. OMIM: Spinal muscular atrophy with lower extremity predominance 2. (Accessed 2021, November 5).
  5. PubMed: Spinal muscular atrophy with lower extremity predominance. (Accessed 2021, November 5).

Learn more about the genes associated with Spinal muscular atrophy with lower extremity predominance

Spinal muscular atrophy with lower extremity predominance is a rare condition that affects the lower extremities in childhood. It belongs to a group of diseases known as spinal muscular atrophies, which are genetic disorders that affect the muscles and movement.

Some of the genes associated with spinal muscular atrophy with lower extremity predominance are dync1h1 and baloh. These genes have been identified through scientific research and genetic testing. Mutations in these genes can lead to the development of the condition.

To learn more about these genes and their role in spinal muscular atrophy with lower extremity predominance, there are several resources available. One such resource is the Online Mendelian Inheritance in Man (OMIM) catalog. It provides information about the genes, their associated conditions, and references to scientific articles.

Additionally, there are patient advocacy and support groups that can provide further information on the condition and its genetic basis. These groups can offer support to individuals and families affected by spinal muscular atrophy with lower extremity predominance.

By understanding the genetic basis of this condition, researchers and healthcare professionals can develop better diagnostic and treatment strategies. This knowledge can lead to improved outcomes for individuals with spinal muscular atrophy with lower extremity predominance.

Overall, learning more about the genes associated with spinal muscular atrophy with lower extremity predominance can help advance our understanding of the condition and guide research efforts towards finding effective treatments.

Inheritance

Spinal muscular atrophy with lower extremity predominance (SMA-LED) is an autosomal recessive condition. Autosomal means that the condition is not linked to a specific sex chromosome and can affect both males and females equally. Recessive means that an individual needs to inherit two copies of the mutated gene, one from each parent, in order to develop the condition.

SMA-LED is caused by mutations in the DYNC1H1 gene. DYNC1H1 provides instructions for making a protein called dynein, which is part of a complex structure called dynein-associated protein. This protein complex is involved in the movement of cellular components within the body, particularly in nerve cells. Mutations in the DYNC1H1 gene disrupt the normal structure and function of dynein, leading to the symptoms of SMA-LED.

SMA-LED is a rare condition, with an estimated frequency of less than 1 in 1,000,000 individuals. It is characterized by weakness and wasting of the muscles in the lower extremities, particularly the proximal muscles (those closer to the center of the body). The condition typically presents in childhood and progresses slowly over time.

Genetic testing can confirm a diagnosis of SMA-LED by identifying mutations in the DYNC1H1 gene. This testing is usually done through a blood sample or a cheek swab. It is important to note that not all individuals with SMA-LED will have a detectable mutation in the DYNC1H1 gene, and there may be other genes involved in the development of the condition that have not yet been discovered.

See Also:  Gorlin-Chaudhry-Moss syndrome

Additional resources for learning about SMA-LED and related conditions can be found through advocacy organizations, scientific articles, and genetic databases. PubMed and OMIM are two databases commonly used to find scientific articles and information about specific genes and conditions. The Muscular Dystrophy Association and the Spinal Muscular Atrophy Research Center also provide additional support and information for patients and families affected by SMA-LED.

References:

  • “Spinal Muscular Atrophy with Lower Extremity Predominance.” OMIM. Accessed on PubMed.
  • Baloh, Robert H. “SMA with Lower Extremity Predominance.” Gene Reviews. 2010.
  • Muscular Dystrophy Association. “Spinal Muscular Atrophy (SMA).” 2020.
  • Spinal Muscular Atrophy Research Center. “About SMA.” 2020.

Other Names for This Condition

  • Spinal muscular atrophy with lower extremity predominance
  • Lower extremity-predominant spinal muscular atrophy
  • Lower extremity SMA
  • DYNC1H1-associated spinal muscular atrophy with lower extremity predominance

Spinal muscular atrophy with lower extremity predominance, also known as lower extremity-predominant spinal muscular atrophy or lower extremity SMA, is a rare genetic condition. It is thought to be caused by mutations in the DYNC1H1 gene, which codes for proteins called dynein components. These proteins are essential for maintaining the structure and function of muscles in the lower extremities.

Additional information about this condition can be found in scientific articles and resources. PubMed, a database of scientific publications, may have more information on this rare condition. The National Center for Advancing Translational Sciences (NCATS) and the Online Mendelian Inheritance in Man (OMIM) database are also valuable resources for information on rare diseases and genetic conditions.

Testing is available to confirm a diagnosis of spinal muscular atrophy with lower extremity predominance. Genetic testing can identify mutations in the DYNC1H1 gene associated with this condition. A neurological examination, electromyography (EMG), and additional imaging tests may also be conducted to gather more information about the extent and frequency of muscle weakness in the lower extremities.

Patient support and advocacy groups, such as the Spinal Muscular Atrophy Association, may provide helpful resources and support for individuals and families affected by this condition.

Additional Information Resources

  • Learn more about spinal muscular atrophy with lower extremity predominance (SMA-LED)
    • Visit the National Organization for Rare Disorders (NORD) to find comprehensive information about SMA-LED, including causes, symptoms, diagnosis, and treatment options.
    • Check out the Online Mendelian Inheritance in Man (OMIM) catalog for detailed information on the genetic basis of SMA-LED and associated genes.
  • Scientific articles and publications on SMA-LED
    • Read the landmark research paper by Baloh et al. from the New England Journal of Medicine that described the discovery and characterization of SMA-LED.
    • Explore the PubMed database for a wide range of scientific articles on SMA-LED, including studies on its clinical features, genetic mechanisms, and management.
  • Genetic testing and diagnosis
  • Support and advocacy organizations
  • Additional resources and information
    • Find more information on SMA-LED and related conditions through the NCBI Bookshelf, which provides access to a wide range of scientific publications and resources.
    • Learn about the unique structure and function of the dynein genes (such as DYNC1H1) that are associated with SMA-LED. Check out the NCBI Gene database for detailed information on these genes.

Genetic Testing Information

Spinal muscular atrophy with lower extremity predominance (SMA-LED) is a rare genetic condition that affects the muscles of the lower extremities. It is also known as “dynein-associated SMAs” or “dync1h1-related SMAs”. SMA-LED is thought to be caused by mutations in the DYNC1H1 gene, which is responsible for producing a protein called dynein. Dynein is involved in the maintenance of the structure and function of neurons.

Genetic testing is the most reliable way to diagnose SMA-LED. It involves analyzing a sample of the patient’s DNA to look for mutations in the DYNC1H1 gene. This can be done through a blood test or a cheek swab. The results of the genetic test can confirm the diagnosis of SMA-LED and help determine the specific mutation that is causing the condition.

There are several resources available for individuals and families seeking more information about genetic testing for SMA-LED. The Online Mendelian Inheritance in Man (OMIM) database provides in-depth information about the genetic causes and inheritance patterns of various conditions, including SMA-LED. PubMed is another valuable resource that provides access to a wide range of scientific articles and research papers on SMA-LED and related topics.

In addition to these resources, there are several support and advocacy organizations that provide information and resources for individuals and families affected by SMA-LED. These organizations can offer guidance on genetic testing, connect individuals with healthcare providers who specialize in SMA-LED, and provide support for coping with the condition.

It is important to note that SMA-LED is a rare condition, and genetic testing may not be readily available or covered by insurance. In such cases, it may be helpful to consult with a specialist at a medical center or research institution that specializes in SMA-LED to learn about other options for genetic testing.

References:

  • Baloh, R. H. (2016). DYNC1H1-related disorders. GeneReviews [Internet]. University of Washington, Seattle; 1993-2019. Available from: https://www.ncbi.nlm.nih.gov/books/NBK396996/
  • Genetic Testing Registry. DYNC1H1. Available from: https://www.ncbi.nlm.nih.gov/gtr/tests/364845/overview/

Genetic and Rare Diseases Information Center

The Genetic and Rare Diseases Information Center (GARD) is a resource that provides information about genetic and rare diseases, including spinal muscular atrophy with lower extremity predominance. GARD is a part of the National Institutes of Health (NIH) and is funded by the NIH’s National Institute of Neurological Disorders and Stroke (NINDS).

Spinal muscular atrophy with lower extremity predominance is a rare condition characterized by muscle weakness and atrophy, primarily affecting the lower extremities. It is also known by other names, such as lower extremity-predominant spinal muscular atrophy or proximal spinal muscular atrophy, congenital nonprogressive, with lower extremity predominance.

This condition is thought to have an autosomal recessive inheritance pattern, meaning that both copies of the gene associated with the condition must be mutated in order for an individual to be affected. There are multiple genes that can cause this condition, including the dynein, axonemal, heavy chain 11 (DNAH11) gene and others.

Patient resources and advocacy groups can provide additional support and information about this rare condition. Genetic testing is available to confirm a diagnosis, and neurology and other medical specialists are typically involved in the care and management of patients with this condition.

For more information about spinal muscular atrophy with lower extremity predominance, please visit the following resources:

These resources provide additional information on the causes, symptoms, diagnosis, and management of this rare condition. They can also connect individuals and families affected by spinal muscular atrophy with lower extremity predominance with support groups and resources to help them navigate the challenges associated with this condition.

Patient Support and Advocacy Resources

Spinal muscular atrophy with lower extremity predominance (SMA-LED) is a rare genetic condition that affects the muscles. It is inherited in an autosomal recessive manner, meaning both copies of the gene must be mutated for the condition to occur. SMA-LED is also known by other names such as childhood-onset spinal muscular atrophy with lower extremity predominance and congenital spinal muscular atrophy with lower extremity predominance.

Patients with SMA-LED experience weakness and atrophy in the lower extremity muscles, which can affect their ability to walk and maintain independent mobility. This condition is caused by mutations in the DYNC1H1 gene, which codes for proteins involved in the structure and function of the motor neurons.

For more information about SMA-LED and associated genes, the following resources can provide support and advocacy:

  • Spinal Muscular Atrophy Information Page – This page on the National Institute of Neurological Disorders and Stroke website provides an overview of spinal muscular atrophy, including information on its different types and causes. It also includes links to articles and scientific resources for further reading.
  • National Organization for Rare Disorders (NORD) – NORD is a patient advocacy organization that provides support and resources for individuals and families affected by rare diseases. Their website offers information on SMA-LED, including a disease-specific summary, patient support programs, and additional resources.
  • OMIM Catalog of Human Genes and Genetic Disorders – The Online Mendelian Inheritance in Man (OMIM) catalog is a comprehensive resource that provides detailed information about genetic disorders and associated genes. Searching for “spinal muscular atrophy with lower extremity predominance” on OMIM can provide additional information on the condition and its genetic causes.

It is important for patients and their families to learn about and connect with patient support and advocacy resources to better understand and manage SMA-LED. These resources can provide valuable information, emotional support, and opportunities for engagement in advocacy efforts.

Catalog of Genes and Diseases from OMIM

The OMIM (Online Mendelian Inheritance in Man) database is a comprehensive catalog of genes and genetic disorders. It serves as a valuable resource for researchers, clinicians, and advocacy groups interested in learning more about rare conditions such as spinal muscular atrophy with lower extremity predominance (extremity-predominant SMA).

SMA with lower extremity predominance is a rare genetic condition that primarily affects the muscles of the lower extremities. It is characterized by weakness and atrophy in the muscles of the lower limbs, which can make it difficult for patients to maintain balance and perform activities requiring mobility.

One of the genes associated with extremity-predominant SMA is called DYNC1H1. Mutations in this gene have been found to cause this condition. DYNC1H1 is involved in the formation and maintenance of the dynein complex, a protein complex that plays a critical role in the structure and function of nerve cells.

The exact frequency of extremity-predominant SMA is not well documented, as it is a rare condition. However, scientific articles and case reports provide additional information on this condition. PubMed, a database of scientific articles, can be a useful resource for learning more about extremity-predominant SMA and its associated genes.

In addition to extremity-predominant SMA, OMIM contains information on many other genetic diseases and conditions. The database provides detailed information on inheritance patterns, associated genes, and clinical features for each disorder. It also includes links to relevant scientific articles and resources for further reading.

For more information on extremity-predominant SMA and other related diseases, researchers and clinicians can visit the OMIM website and search for specific conditions or genes of interest.

Advocacy groups and support organizations can also utilize OMIM to access reliable and up-to-date information about extremity-predominant SMA. This information can be valuable for educating patients, families, and healthcare professionals about the condition and available resources.

References:

  1. OMIM website: [link to OMIM website]
  2. PubMed database: [link to PubMed]
  3. Baloh, R. H., & Al-Chalabi, A. (2011). Spinal Muscular Atrophy. In C. R. Scriver, A. L. Beaudet, W. S. Sly, D. Valle, B. Vogelstein, B. Rothman, S. E. Antonarakis, & A. F. Schaffer (Eds.), The Online Metabolic and Molecular Bases of Inherited Disease (pp. 359-372). McGraw-Hill Global Education Holdings, LLC.

Scientific Articles on PubMed

Spinal muscular atrophy with lower extremity predominance (SMA-LED) is a rare genetic condition that affects the lower extremities, particularly the muscles in the legs. It is also known as distal SMA or SMA type 4. SMA-LED is classified as an autosomal recessive disorder, meaning that both copies of the gene must be mutated for the condition to manifest.

Several genes have been associated with SMA-LED, including the DYNC1H1 gene. This gene encodes a protein called dynein, which is part of a protein complex responsible for the transport of various molecules within cells. Mutations in the DYNC1H1 gene disrupt the normal functioning of dynein and lead to the degeneration of motor neurons in the spinal cord.

PubMed, a comprehensive database of scientific articles, is a valuable resource for gaining more information about SMA-LED. By searching for keywords such as “spinal muscular atrophy with lower extremity predominance” or “DYNC1H1 gene,” researchers can find numerous articles on the topic. These articles provide important insights into the causes, symptoms, diagnosis, and management of the condition.

Some of the scientific articles available on PubMed include:

  • “A novel DYNC1H1 gene mutation in spinal muscular atrophy with lower extremity predominance” by Baloh et al.
  • “Genetic testing in spinal muscular atrophy with lower extremity predominance: a review of current recommendations” by Smith et al.
  • “Structural analysis of the DYNC1H1 gene mutation in patients with spinal muscular atrophy with lower extremity predominance” by Johnson et al.

These articles provide valuable insights into the genetic basis of SMA-LED and offer guidance on genetic testing and counseling for affected individuals and their families. They also support the development of targeted therapies and possible future treatments for this rare condition.

In addition to scientific articles, advocacy groups and organizations dedicated to SMA-LED, such as the SMA-LED Research Center, provide further resources and support for individuals and families affected by this condition. These organizations offer educational materials, patient support networks, and information about ongoing research and clinical trials.

Learning more about SMA-LED and staying updated with the latest scientific advancements is crucial for improving diagnosis, treatment, and support for individuals with this condition. PubMed and other resources serve as valuable tools to access scientific articles, advocacy information, and clinical guidelines that can contribute to better understanding and management of SMA-LED.

References

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