Usher Syndrome

Jump to: Causes| Genetics & Inheritance |Symptoms| Diagnosis| Treatment & Care| Research & Clinical Trials| Resources

overview

Usher syndrome is a rare genetic condition that affects hearing and vision, and sometimes balance. It is the most common cause of inherited deaf-blindness, affecting about 4 to 17 out of every 100,000 people. [1]

People with Usher Syndrome are born or develop hearing loss early in life. Over time, they also lose vision because of a condition called retinitis pigmentosa (RP). There are three main types of Usher syndrome, which differ in severity and when symptoms begin.

CAUSES

Usher syndrome is caused by changes in how certain cells in the eyes and ears develop and function. These cells normally turn light and sound into signals that the brain can understand. When they don’t work properly, it leads to vision loss, hearing loss, and sometimes balance problems.

In the eyes, Usher syndrome causes damage to the retina, the light-sensing layer at the back of the eye. Over time, the photoreceptor cells—rods and cones—stop working the way they should. Rods help with night and side vision, while cones support central and colour vision. As these cells break down, a person’s ability to see gradually decreases.

In the ears, Usher syndrome affects tiny sensory cells in the inner ear called hair cells. These cells detect sound vibrations and help send sound information to the brain. When they are damaged or missing, hearing becomes reduced or unclear. The parts of the inner ear that help with balance can also be affected, which is why some people experience unsteadiness or dizziness.

These problems happen because of underlying changes in specific genes that guide how these eye and ear cells work.

genetics & inheritance

Usher syndrome is a genetic disorder, which means it is caused by changes (mutations) in specific genes. These genes help make proteins that are important for healthy vision and hearing. When a gene has a mutation, it can produce faulty proteins that don’t work properly and damage cells in the retina and inner ear.

Usher syndrome is passed down through families in an autosomal recessive pattern. This means a person must inherit one faulty copy of the gene from each parent in order to have the disease. If they only inherit one faulty copy, they won’t have the condition but can pass the gene mutation to their children.

Different types of Usher syndrome are caused by mutations in different genes. Researchers have discovered at least 9 genes that can lead to Usher Syndrome [2].

• Type 1: Most often caused by mutations in the MYO7A, CDH23, USH1C, PCDH15, or USH1G genes
• Type 2: Usually caused by mutations in the USH2A, GPR98, or WHRN genes
• Type 3: Caused by mutations in the CLRN1 gene.

Each of these genes plays a role in helping the cells in the eyes and ears communicate with the brain. When the genes are not working, those signals are weak or lost.

Genetic testing can often identify which gene is affected. This can help with diagnosis and guide treatment plans. It may also help determine if someone qualifies for clinical trials or emerging therapies.

symptoms

Usher syndrome affects vision, hearing, and sometimes balance. Vision symptoms are caused by the breakdown of photoreceptor cells in the retina and tend to get worse over time. Although symptoms vary, many people first notice night blindness, followed by a gradual loss of peripheral (side) vision, which can lead to tunnel vision. Central and colour vision may also decline as the condition progresses.

Doctors divide Usher syndrome into three main types, which helps explain when symptoms usually begin and how quickly they may change.

Type 1 (most severe)

Vision: Vision problems start in early childhood. Night blindness is often the first sign. Side vision gradually decreases, and many people develop tunnel vision by adolescence or early adulthood.
Hearing & Balance: Severe hearing loss or deafness is present from birth. Balance problems begin early because the inner ear does not work normally.

Type 2

Vision: Vision loss usually begins later—often in late childhood or the teen years. Night blindness appears first, followed by a gradual loss of peripheral vision. Significant vision loss typically develops by adulthood.
Hearing & Balance: Moderate to severe hearing loss from birth, but speech and language often develop more typically with early support. Balance is usually normal.

Type 3

Vision: Vision changes vary widely. Many people notice night blindness in their teens, with peripheral and central vision decreasing over time. Most experience serious vision loss by adulthood, but the speed of progression can differ greatly.
Hearing & Balance: Hearing is normal at birth but decreases over childhood or teenage years. May be normal at first but can worsen with age.

diagnosis

Usher syndrome is usually diagnosed using a combination of hearing, vision, balance, and genetic tests. These tests help doctors understand how the eyes and ears are working and what might be causing the problems.

• Electroretinography (ERG): Measures how the retina responds to light. Special drops are used to prepare the eyes, and a contact lens or thin wire is placed on the eye. The test takes place in a dark room and uses light flashes to test how well the rod and cone photoreceptor cells are working.
• Visual field test: Measures how much of the person’s side (peripheral) vision is working. The person looks into a machine that flashes small lights and responds when they see them. This test can find early signs of vision loss from retinitis pigmentosa.
• Optical coherence tomography (OCT): A special camera takes high-resolution pictures of the layers of the retina. This helps doctors see any damage or changes in the retina.
• Hearing tests (audiology): Checks how well a person can hear different sounds and volumes. This is often the first step, especially if hearing loss is noticed early in life.
• Balance tests: These check how well the inner ear is helping with balance. They may be used if there are signs of dizziness or poor coordination.
• Genetic testing: Identifies the exact gene changes (mutations) that are causing the condition. This can confirm a diagnosis and help guide future care or participation in research.
• Genetic counselling: While not a test itself, genetic counselling helps families understand how Usher syndrome is inherited, the chances of passing it on, and what test results mean.

treatment & care

There is currently no cure for Usher syndrome, but there are many ways to manage symptoms and improve quality of life. Early diagnosis is important so that care plans, educational support, and communication tools can be put in place early.

• Vision Support: There are currently no approved treatments for RP and the vision loss caused by Usher syndrome. Use of low-vision aids (like magnifiers or screen readers), UV-blocking sunglasses, and vision rehabilitation services can help increase independence. A diet rich in leafy greens, fruits, omega-3s, and possibly antioxidants or lutein may help slow progression of vision loss. Always speak with your doctor before adding supplements or vitamins to your routine.
• Hearing Support: Use of hearing aids, cochlear implants, assistive listening devices, auditory training, or learning sign language to improve hearing and communication.
• Balance Support: Participation in balance therapy or physical therapy to improve coordination, especially for people with Type 1 Usher syndrome.
• Support Services: Access to independent-living training, special education programs, counselling, and peer support groups to build skills, confidence, and emotional well-being

Research & Clinical Trials

Many research groups are working to develop new treatments for Usher syndrome. These include treatments that protect vision, correct the faulty genes, and even restore sight and hearing.

Some of the most promising areas of vision research include:

• Gene and RNA therapies: These aim to fix or replace the faulty genes that cause Usher syndrome. Some early trials have shown promise for people with USH2A and MYO7A gene changes.
• Stem cell therapy: Researchers are studying whether stem cells can replace damaged cells in the eye and restore vision in people with retinal diseases like Usher syndrome.
• Optogenetics: This approach uses special light-sensitive genes to help cells in the retina respond to light again, even after major vision loss.
• Protective therapies: These treatments aim to slow down the loss of vision and hearing. One example is a drug called N-acetylcysteine, which is now being tested in a clinical trial in Canada.
• Bionic eyes (retinal prostheses): These devices may help people with severe vision loss regain some ability to see light and shapes.

Discover more information on clinical trials for Usher Syndrome. 

Resources

Fighting Blindness Canada has developed resources to help you navigate vision care. Follow the links below to learn more. 

• Sign up for our e-newsletter to keep up to date on the latest breakthroughs and community events. 
• Contact our Heath Information line by email or phone to ask questions about your eye health. 
• Hear about the latest in vision research and connect with others at our View Point educational series.
• Learn about genetic testing and join our Inherited Retinal Disease Patient Registry to connect with clinical trials and treatments. 
• Discover more information on clinical trials for Usher Syndrome.
• Learn more about all of Fighting Blindness Canada’s funded research.

References

[1] https://www.nidcd.nih.gov/health/usher-syndrome

[2] https://www.nei.nih.gov/learn-about-eye-health/eye-conditions-and-diseases/usher-syndrome/genes-and-usher-syndrome

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Last updated September 30, 2025.