Usher syndrome is an inherited condition that leads to hearing and vision loss that worsens over time. Partial or total hearing loss occurs due to abnormalities in the inner ear (sensorineural). Vision loss is the result of retinitis pigmentosa, an eye disease that affects the light-sensitive layer of cells at the back of the eye (retina). Usher syndrome is classified into types I, II and III, based on the severity of hearing loss, balance problems, and the age of onset.
Usher syndrome type 3A (USH3A) is rare and is caused by genetic variation in the CLRN1 gene, which inhibits the function of the clarin 1 protein. This protein is found in hair cells in the ear and photoreceptors in the eyes and plays an important role in normal hearing and vision.
Take this test to find out if you are a carrier of the CLRN1 variant and are at risk of passing it to your children.
USH3A is caused by genetic variation in the CLRN1 gene. This gene gives instructions for the clarin 1 protein involved in hearing and vision. Affected individuals produce a defective clarin 1 protein, leading to the hearing and vision loss associated with the disease.
USH3A is inherited in an autosomal recessive pattern, which means two defective copies of the CLRN1 gene must be inherited in order for the disease to manifest.
This test detects one genetic variant in the CLRN1 gene which causes USH3A.
- rs111033258 A (N48K)
Understanding your carrier status will help you understand the risk of passing this variant to your children.
Characteristic symptoms include:
- Hearing loss that appears in late childhood or early teens, usually leading to profound deafness by middle age
- Gradual vision loss (retinitis pigmentosa)
- May have balance issues
- Life expectancy and intelligence are not affected
How It Works
Step 1: Sign up for a free DNA Access account.
Step 2: Upload your DNA markers to DNA Access.
Step 3: Log in to your account to access your results when they are ready.