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Questions about rare diseases?
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Disease Information

Summary
Hexosaminidase A deficiency results in a group of neurodegenerative disorders caused by intralysosomal storage of the specific glycosphingolipid, GM2 ganglioside. The prototype hexosaminidase A deficiency is Tay-Sachs disease, also known as the acute infantile variant. Tay-Sachs disease is characterized by progressive weakness, loss of motor skills, decreased attentiveness, and increased startle response beginning between ages three and six months with progressive evidence of neurodegeneration including: seizures, blindness, spasticity, eventual total incapacitation, and death, usually before age four years. The juvenile (subacute), chronic, and adult-onset variants of hexosaminidase A deficiency have later onsets, slower progression, and more variable neurologic findings, including: progressive dystonia, spinocerebellar degeneration, motor neuron disease, and, in some individuals with adult-onset disease, a bipolar form of psychosis.
Summary
Hexosaminidase A deficiency results in a group of neurodegenerative disorders caused by intralysosomal storage of the specific glycosphingolipid, GM2 ganglioside. The prototype hexosaminidase A deficiency is Tay-Sachs disease, also known as the acute infantile variant. Tay-Sachs disease is characterized by progressive weakness, loss of motor skills, decreased attentiveness, and increased startle response beginning between ages three and six months with progressive evidence of neurodegeneration including: seizures, blindness, spasticity, eventual total incapacitation, and death, usually before age four years. The juvenile (subacute), chronic, and adult-onset variants of hexosaminidase A deficiency have later onsets, slower progression, and more variable neurologic findings, including: progressive dystonia, spinocerebellar degeneration, motor neuron disease, and, in some individuals with adult-onset disease, a bipolar form of psychosis.
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Resource(s) for Medical Professionals and Scientists on This Disease:
  • GeneReviews  provides clinical information on genetic diseases, including diagnosis, treatment, and genetic counseling.

About GM2-gangliosidosis, B, B1, AB variant

Many rare diseases have limited information. Currently, GARD aims to provide the following information for this disease:

  • Population Estimate:This section is currently indevelopment.
  • Symptoms:This section is currently in development.
  • Cause:GARD does not currently have information about the cause of this disease.
  • Organizations:Patient organizations are available to help find a specialist, or advocacy and support for this specific disease.

Causes

GARD does not currently have information about the cause of this disease.

When Do Symptoms of GM2-gangliosidosis, B, B1, AB variant Begin?

This section is currently in development.

Symptoms

This section is currently in development.

Diagnostic Journey

On average, it takes more than six years to receive an accurate rare disease diagnosis. Many primary care providers (PCPs) may not be familiar with rare diseases, and you may need to see multiple specialists to reach the correct diagnosis. However, advocating for yourself with your healthcare team may help speed your time to diagnosis. To combat common challenges, be prepared:

  • Find disease-specific information to discuss with your healthcare providers.
  • Ask for diagnostic tests.
  • Request referrals to specialists.

Knowing where to start your diagnostic journey and how to navigate the next steps are critical to speeding your time to diagnosis

Your Diagnostic Team

How can a diagnostic team help?

Establishing care with a dedicated primary care provider (PCP) is an important early step in your rare disease journey. A PCP can help improve care and shorten the time to diagnosis by providing referrals to the appropriate specialists. These specialists, with advanced training in different body systems or types of diseases, can offer the specialized diagnostic procedures you need.

Use this tool by Medicare to find a PCP in your area by inputting your location and keyword "Primary Care Provider."

 

Multidisciplinary Care Centers

Is it time to find a multidisciplinary care center?

If you've visited your PCP, met with specialists, and undergone the recommended tests, but still do not have a confirmed diagnosis, it may be time to visit a multidisciplinary care center. Multidisciplinary care centers are usually teaching, university, or research hospitals that have teams of medical experts and specialists working together in the same location. This means a wide range of diagnostic tests and clinical knowledge are available at one facility, which can help increase communication and collaboration among your care team. The additional resources often available at multidisciplinary centers may help speed the time to diagnosis for rare diseases.



Multidisciplinary Care Centers

Is it time to find a multidisciplinary care center?

If you've visited your PCP, met with specialists, and undergone the recommended tests, but still do not have a confirmed diagnosis, it may be time to visit a multidisciplinary care center. Multidisciplinary care centers are usually teaching, university, or research hospitals that have teams of medical experts and specialists working together in the same location. This means a wide range of diagnostic tests and clinical knowledge are available at one facility, which can help increase communication and collaboration among your care team. The additional resources often available at multidisciplinary centers may help speed the time to diagnosis for rare diseases.



Rare Disease Experts

How can you find a rare disease expert?

If a diagnosis remains unknown despite extensive efforts by your PCP and specialists, it can be challenging to know what kind of expert you may need or where to find one. A rare disease expert is a care provider that has knowledge or training on specific disease(s), but there may only be a few experts in your state, region, or country. Rare disease experts may work at large research or teaching hospitals. In complex cases, coordinating with a network of experts can help your care provider find the right diagnosis. 
Contact a GARD Information Specialist for help finding an expert.

You can ask your care providers for help finding an expert or use directory tools to search for experts near you. The National Organization for Rare Disorders (NORD) maintains a list of rare disease centers with experts that work together to find treatments and cures for a broad range of rare diseases. Search NORD's Center Directory to find experts near you.

Rare Disease Experts

How can you find a rare disease expert?

If a diagnosis remains unknown despite extensive efforts by your PCP and specialists, it can be challenging to know what kind of expert you may need or where to find one. A rare disease expert is a care provider that has knowledge or training on specific disease(s), but there may only be a few experts in your state, region, or country. Rare disease experts may work at large research or teaching hospitals. In complex cases, coordinating with a network of experts can help your care provider find the right diagnosis. 
Contact a GARD Information Specialist for help finding an expert.

You can ask your care providers for help finding an expert or use directory tools to search for experts near you. The National Organization for Rare Disorders (NORD) maintains a list of rare disease centers with experts that work together to find treatments and cures for a broad range of rare diseases. Search NORD's Center Directory to find experts near you.
 

Find Your Community

How Can Patient Organizations Help?

Patient organizations can help patients and families connect. They build public awareness of the disease and are a driving force behind research to improve patients' lives. They may offer online and in-person resources to help people live well with their disease. Many collaborate with medical experts and researchers.

Services of patient organizations differ, but may include:

  • Ways to connect to others and share personal stories
  • Easy-to-read information
  • Up-to-date treatment and research information
  • Patient registries
  • Lists of specialists or specialty centers
  • Financial aid and travel resources

Please note: GARD provides organizations for informational purposes only and not as an endorsement of their services. Please contact an organization directly if you have questions about the information or resources it provides.

View GARD's criteria for including patient organizations, which can be found under the FAQs on our About page. Request an update or to have your organization added to GARD.

Patient Organizations

5 Organizations

Organization Name

Who They Serve

Helpful Links

Country

Alex The Leukodystrophy Charity
People With

GM2-gangliosidosis, B, B1, AB variant

Helpful Links
Country

United Kingdom

EveryLife Foundation for Rare Diseases
People With

Rare Diseases

Helpful Links
Country

United States

Genetic Alliance
People With

Rare Diseases

Helpful Links
Country

United States

Global Genes
People With

Rare Diseases

Helpful Links
Country

United States

National Organization for Rare Disorders
People With

Rare Diseases

Helpful Links
Country

United States

Participate in Research

Clinical studies are part of clinical research and play an important role in medical advances, including for rare diseases. Through clinical studies, researchers may ultimately uncover better ways to treat, prevent, diagnose, and understand human diseases.

What Are Clinical Studies?

Clinical studies are medical research involving people as participants. There are two main types of clinical studies:

  1. Clinical trials determine if a new test or treatment for a disease is effective and safe by comparing groups receiving different tests/treatments.
  2. Observational studies involve recording changes over time among a specific group of people in their natural settings.
Learn more about clinical trials from this U.S. Food & Drug Administration webpage.

Why Participate in Clinical Studies?

People participate in clinical trials for many reasons. People with a disease may participate to receive the newest possible treatment and additional care from clinical study staff as well as to help others living with the same or similar disease. Healthy volunteers may participate to help others and to contribute to moving science forward.

To find the right clinical study we recommend you consult your doctors, other trusted medical professionals, and patient organizations. Additionally, you can use ClinicalTrials.gov to search for clinical studies by disease, terms, or location.

What if There Are No Available Clinical Studies?

ResearchMatch helps connect people interested in research studies  with researchers from top medical centers across the United States. Anyone from the U.S. can register with this free program funded by NIH. Researchers from participating institutions use the database to search for and invite patients or healthy volunteers who meet their study criteria to participate.

Join the All of Us Research Program!

The All of Us Research Program is inviting 1 million people from all backgrounds across the U.S. to help build one of the most diverse health databases in history. Researchers will use the data to learn how our biology, lifestyle, and environment affect health. This may one day help them find ways to treat and prevent diseases.

What Are Clinical Studies?

Clinical studies are medical research involving people as participants. There are two main types of clinical studies:
  1. Clinical trials determine if a new test or treatment for a disease is effective and safe by comparing groups receiving different tests/treatments.
  2. Observational studies involve recording changes over time among a specific group of people in their natural settings.
Learn more about clinical trials from this U.S. Food & Drug Administration webpage.
Read More

Why Participate in Clinical Studies?

People participate in clinical trials for many reasons. People with a disease may participate to receive the newest possible treatment and additional care from clinical study staff as well as to help others living with the same or similar disease. Healthy volunteers may participate to help others and to contribute to moving science forward.

To find the right clinical study we recommend you consult your doctors, other trusted medical professionals, and patient organizations. Additionally, you can use ClinicalTrials.gov to search for clinical studies by disease, terms, or location.
Read More

What if There Are No Available Clinical Studies?

ResearchMatch helps connect people interested in research studies  with researchers from top medical centers across the United States. Anyone from the U.S. can register with this free program funded by NIH. Researchers from participating institutions use the database to search for and invite patients or healthy volunteers who meet their study criteria to participate.

Join the All of Us Research Program!

The All of Us Research Program is inviting 1 million people from all backgrounds across the U.S. to help build one of the most diverse health databases in history. Researchers will use the data to learn how our biology, lifestyle, and environment affect health. This may one day help them find ways to treat and prevent diseases.

ClinicalTrials.gov, an affiliate of NIH, provides current information on clinical research studies in the United States and abroad. Talk to a trusted doctor before choosing to participate in any clinical study. We recommend checking this site often and searching for studies with related terms/synonyms to improve results.
Search ClinicalTrials.gov for this disease
Contact a GARD Information Specialist if you need help finding more information on this rare disease or available clinical studies. Please note that GARD cannot enroll individuals in clinical studies.
1-888-205-2311
Available toll-free Monday through Friday from 12 pm to 6 pm Eastern Time
(Except: Federal Holidays)
Contact GARD
Use the contact form to send your questions to a GARD Information Specialist.

Please allow 2 to 10 business days for us to respond.
ClinicalTrials.gov, an affiliate of NIH, provides current information on clinical research studies in the United States and abroad. Talk to a trusted doctor before choosing to participate in any clinical study. We recommend checking this site often and searching for studies with related terms/synonyms to improve results.
Search ClinicalTrials.gov for this disease
Contact a GARD Information Specialist if you need help finding more information on this rare disease or available clinical studies. Please note that GARD cannot enroll individuals in clinical studies.
1-888-205-2311
Available toll-free Monday through Friday from 12 pm to 6 pm Eastern Time
(Except: Federal Holidays)
Contact GARD
Use the contact form to send your questions to a GARD Information Specialist.

Please allow 2 to 10 business days for us to respond.

Last Updated: December 2024