Usher Syndrome Type 2c
Disease Details
Family Health Simplified
- Description
- Usher syndrome type 2C is a genetic disorder characterized by moderate to severe hearing loss at birth, normal balance, and progressive vision loss due to retinitis pigmentosa.
- Type
- Usher syndrome type 2C is an autosomal recessive genetic disorder. This means that an individual must inherit two copies of the mutated gene, one from each parent, to be affected by the condition.
- Signs And Symptoms
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Usher syndrome type 2C is a genetic disorder characterized by:
**Signs and Symptoms:**
1. **Hearing Loss:** Moderate to severe congenital hearing loss that is typically non-progressive.
2. **Retinitis Pigmentosa:** Progressive vision loss due to retinal degeneration, usually starting in adolescence. This includes night blindness and loss of peripheral vision.
3. **Normal Balance:** Unlike other types of Usher syndrome, this type generally does not affect balance.
If you need further details, feel free to ask. - Prognosis
- Usher syndrome type 2C is a genetic disorder characterized by moderate to severe hearing loss at birth and progressive vision loss due to retinitis pigmentosa. The prognosis for individuals with this subtype often includes stable hearing impairment that does not worsen over time, unlike vision loss which typically progresses and can lead to significant visual impairment or blindness. The condition can also sometimes be associated with balance issues. Early diagnosis and intervention, such as the use of hearing aids and low-vision aids, can improve quality of life. Ongoing research may offer future avenues for treatment and management of this condition.
- Onset
- Usher syndrome type 2C typically manifests with congenital, moderate-to-severe sensorineural hearing loss and progressive vision loss due to retinitis pigmentosa. However, the exact age of onset for vision impairment can vary among individuals.
- Prevalence
- The prevalence of Usher Syndrome Type 2C is not well-documented specifically, but Usher syndrome overall is considered a rare disorder, affecting approximately 3 to 6 in 100,000 people worldwide.
- Epidemiology
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Epidemiology:
Usher syndrome type 2C (USH2C) is a rare genetic disorder, with specific prevalence difficult to ascertain due to its rarity. Usher syndrome as a whole affects approximately 4 to 17 per 100,000 individuals globally. It is characterized by moderate to severe hearing loss from birth and progressive vision loss due to retinitis pigmentosa, typically starting in late adolescence or adulthood. Type 2, including 2C, generally involves congenital sensorineural hearing loss without balance issues, and the vision loss progresses more slowly than in other types. Usher syndrome type 2C is caused by mutations in the ADGRV1 gene (formerly known as VLGR1 or GPR98).
Nan: This term seems to be incomplete or unclear in this context. "NaN" commonly stands for "Not a Number" in computational fields, but in the context of Usher syndrome, additional context or clarification might be needed to provide a relevant answer. - Intractability
- Usher syndrome type 2C is currently considered intractable, as there is no cure available. Management focuses on alleviating symptoms and providing supportive care. This includes the use of hearing aids, cochlear implants, vision aids, and educational support to improve the quality of life for affected individuals.
- Disease Severity
- Usher syndrome type 2C is a relatively less severe form of Usher syndrome compared to type 1. Individuals with this condition typically experience moderate to severe hearing loss from birth and develop retinitis pigmentosa later in life, which leads to progressive vision loss. Unlike type 1, there are no balance issues associated with type 2C. No specific association with "nan" is noted in typical clinical descriptions of this subtype.
- Healthcare Professionals
- Disease Ontology ID - DOID:0110839
- Pathophysiology
- Usher syndrome type 2C is a subtype of Usher syndrome, a genetic disorder causing hearing loss and vision impairment. The pathophysiology involves mutations in the GPR98 gene, which encodes the protein usherin. Usherin is crucial for the proper development and function of the inner ear and the retina. Mutations in this gene disrupt the structure and function of these tissues, leading to sensorineural hearing loss from birth or early childhood and progressive vision loss due to retinitis pigmentosa, typically manifesting in adolescence or early adulthood.
- Carrier Status
- For Usher syndrome type 2C, carrier status refers to an individual who has one mutated copy and one normal copy of the USH2C gene. Carriers typically do not show symptoms of the disorder but can pass the mutated gene to their offspring. If both parents are carriers, their child has a 25% chance of having Usher syndrome type 2C.
- Mechanism
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Usher Syndrome Type 2C (USH2C) is one of the subtypes of Usher Syndrome, a genetic disorder characterized by hearing loss and progressive vision loss due to retinitis pigmentosa.
**Mechanism:**
Usher Syndrome Type 2C is primarily associated with mutations in the ADGRV1 (also known as GPR98) gene. This gene encodes a large protein called adhesion G protein-coupled receptor V1, which is involved in the development and function of the inner ear and retina.
**Molecular Mechanisms:**
1. **ADGRV1 Protein Function:**
- ADGRV1 is involved in cell-cell adhesion processes, important for the structural integrity of cochlear hair cells in the inner ear and photoreceptor cells in the retina.
- It plays a role in the organization of the stereocilia bundle in cochlear hair cells, crucial for the mechanotransduction process that converts sound waves into electrical signals.
2. **Mutation Effects:**
- Mutations in the ADGRV1 gene can lead to the production of a dysfunctional or truncated protein.
- This disruption in ADGRV1 function impairs the proper development and maintenance of the stereocilia in hair cells and affects the structure and function of photoreceptor cells in the retina.
- The compromised cellular architecture and signaling in these sensory cells lead to the clinical manifestations of hearing loss and progressive vision loss.
3. **Pathophysiology:**
- In the inner ear, defective ADGRV1 results in hair cell malformation or degeneration, leading to sensorineural hearing loss.
- In the retina, the progressive degeneration of photoreceptor cells due to impaired maintenance and cellular stress results in retinitis pigmentosa, characterized by night vision difficulties and peripheral vision loss progressing to central vision loss.
Understanding these molecular mechanisms is crucial for developing potential therapeutic interventions and for genetic counseling. - Treatment
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Usher syndrome type 2C currently has no cure, but treatment focuses on managing symptoms and improving quality of life. Interventions may include:
1. **Hearing Aids:** To assist with varying degrees of hearing loss.
2. **Vision Support:** Use of visual aids, adaptive technologies, and mobility training to cope with progressive vision loss.
3. **Educational Support:** Special education services and support for communication skills development.
4. **Regular Monitoring:** Ongoing ophthalmologic and audiologic assessments to monitor vision and hearing changes.
5. **Genetic Counseling:** For affected individuals and their families. - Compassionate Use Treatment
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Usher Syndrome Type 2C (USH2C) is a genetic disorder that affects both hearing and vision. For compassionate use, off-label, or experimental treatments, the following approaches might be relevant:
1. **Gene Therapy**: Experimental treatments involving gene replacement or editing technologies aim to correct the defective genes responsible for USH2C. Clinical trials may be available for participation.
2. **Cochlear Implants**: While not experimental, cochlear implants are sometimes used off-label to improve hearing in Usher syndrome patients.
3. **Retinal Implants**: These are still experimental and aim to restore some degree of vision in individuals with profound vision loss.
4. **Pharmacological Therapy**: Certain drugs that are not specifically approved for Usher syndrome may be used off-label to manage symptoms or slow disease progression. Clinical trials might be exploring the efficacy of these drugs.
5. **CRISPR and Other Gene Editing Technologies**: Experimental use of CRISPR/Cas9 and other gene editing technologies may offer potential future treatments for correcting the genetic mutations associated with USH2C.
It's essential to consult healthcare providers and genetic counselors for the most current and applicable treatments. - Lifestyle Recommendations
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For Usher syndrome type 2C, which involves a combination of moderate to severe hearing loss and progressive vision loss due to retinitis pigmentosa, lifestyle recommendations include:
1. **Regular Audiological and Ophthalmological Checkups**: Schedule consistent visits to audiologists and ophthalmologists to monitor and manage hearing and vision changes.
2. **Use of Assistive Devices**: Utilize hearing aids, cochlear implants, and visual aids as recommended by healthcare professionals to improve quality of life.
3. **Safety Measures**: Adapt the living environment to enhance safety, such as using adequate lighting, minimizing trip hazards, and installing handrails.
4. **Communication Strategies**: Learn and employ effective communication techniques, such as lip reading, sign language, or using text-based communication tools.
5. **Healthy Diet and Exercise**: Maintain a balanced diet rich in vitamins and minerals that promote eye health (e.g., Vitamin A, Omega-3 fatty acids). Regular physical activity can help maintain overall well-being.
6. **Support Systems**: Engage with support groups and counseling for emotional and psychological support, as coping with sensory loss can be challenging.
7. **Educational Accommodations**: Ensure appropriate accommodations in educational settings, such as captioned videos, note-taking services, or extra time for tasks.
8. **Employment Adaptations**: Seek workplace accommodations, such as specialized equipment or flexible working conditions to optimize job performance and comfort.
Stay proactive in managing the condition, and consult healthcare providers regularly to tailor these recommendations to individual needs. - Medication
- Usher Syndrome Type 2C is a genetic condition characterized by moderate to severe hearing loss from birth and progressive vision loss due to retinitis pigmentosa. Currently, there is no specific medication to treat or cure Usher Syndrome Type 2C. Management focuses on addressing the symptoms, including the use of hearing aids or cochlear implants to help with hearing loss and various supports for vision impairment. Genetic counseling and regular monitoring by healthcare professionals familiar with the syndrome are also recommended.
- Repurposable Drugs
- Currently, there are no specific repurposable drugs identified for Usher syndrome type 2C. Research is ongoing to find potential treatments, but as of now, no established pharmaceuticals have been repurposed for this condition.
- Metabolites
- For Usher syndrome type 2C, no specific metabolites have been directly associated with this condition in the literature. This genetic disorder is characterized by hearing loss and progressive vision loss due to retinitis pigmentosa, but metabolic profiling specific to type 2C is not well-documented. Research focuses primarily on the genetic mutations and resultant sensory deficits.
- Nutraceuticals
- There is no direct evidence that nutraceuticals specifically target Usher Syndrome Type 2C. Usher Syndrome is a genetic disorder, and currently, the focus is primarily on genetic research, gene therapy, and supportive treatments rather than nutraceutical interventions. It is crucial to consult with a healthcare provider for guidance tailored to individual cases.
- Peptides
- For Usher syndrome type 2C, there is no established or widely-recognized peptide-based treatment or therapy as of the latest available research. Usher syndrome type 2C is a genetic disorder characterized by moderate to severe hearing loss and progressive vision loss due to retinitis pigmentosa. No specific peptides have been identified or approved for treating or managing this particular subtype of Usher syndrome. The focus of research is often on gene therapy, cochlear implants, and other supportive treatments.