Usher Syndrome Type 2
Description
Usher Syndrome Type 2 (USH2) is a rare genetic disorder that affects both hearing and vision. It is characterized by progressive hearing loss from birth and retinitis pigmentosa (RP), a degenerative eye disease that causes night blindness and peripheral vision loss. This blog post provides a comprehensive overview of Usher Syndrome Type 2, including its signs and symptoms, causes, inheritance pattern, diagnosis, management strategies, and resources for living a fulfilling life with the condition.
Genes Involved
Genes Involved in Usher Syndrome Type 2:
- USH2A: This gene is the most common cause of Usher Syndrome Type 2, accounting for about 90% of cases.
- MYO7A: Mutations in this gene can also lead to Usher Syndrome Type 2, but it is less common than USH2A.
Recognizing the Signs and Symptoms
Recognizing the Signs and Symptoms of Usher Syndrome Type 2:
- Hearing Loss: Present at birth or developing early in life, usually progressive, impacting both ears.
- Balance Problems: Some individuals may experience balance issues, often due to inner ear involvement.
- Retinitis Pigmentosa (RP): This eye condition starts with night blindness and peripheral vision loss, gradually affecting central vision over time.
- Visual Field Loss: As RP progresses, individuals may experience difficulty with seeing in low light, tunnel vision, and a shrinking field of vision.
- Speech and Language Delays: Due to hearing loss, some children may experience delays in speech and language development.
Causes
Causes of Usher Syndrome Type 2:
Usher Syndrome Type 2 is caused by genetic mutations, specifically in the USH2A and MYO7A genes. These mutations are inherited in an autosomal recessive manner, meaning that both parents must carry the gene mutation for their child to inherit the condition.
Inheritance/recurrence risk
Inheritance or Recurrence Risk of Usher Syndrome Type 2:
- Autosomal Recessive Inheritance: Both parents must carry the mutated gene for their child to inherit Usher Syndrome Type 2. If both parents are carriers, there is a 25% chance with each pregnancy that their child will inherit the condition.
- Recurrence Risk: If a couple has a child with Usher Syndrome Type 2, there is a 25% chance that each subsequent child will also have the condition.