Usher’s Syndrome

Usher’s syndrome is a rare genetic condition that affects both hearing and vision, and is the most common cause of combined deafness and blindness. People with this condition are born with it, though symptoms develop at different times depending on the type. While there is no cure, early identification and proper management can help people live full, independent lives.

Table of contents

• What is Usher’s syndrome?
• Types of Usher’s syndrome
• Symptoms
• What causes Usher’s syndrome?
• How is Usher’s syndrome diagnosed?
• Treatment and management
• Living with Usher’s syndrome
• Current research

What is Usher’s syndrome?

Usher–Hallgren syndrome, retinitis pigmentosa–dysacusis syndrome, dystrophia retinae dysacusis syndrome

Usher’s syndrome is a rare genetic disease that affects both hearing and vision, and sometimes balance.^[1] It is the most common condition that causes combined deafness and blindness.^[8] The condition gets its name from Charles Usher, a British eye doctor who first described how it is passed down in families in 1914.^[5]

People who have Usher’s syndrome are born with it, though they typically receive their diagnosis during childhood or teenage years.^[1] The condition causes deafness or hearing loss and an eye disease called retinitis pigmentosa (RP), which is a breakdown of light-sensing cells in the back of the eye.^[1] Some types of Usher’s syndrome also cause balance problems.

Worldwide, researchers estimate that about 400,000 people have Usher’s syndrome.^[7] The condition affects approximately 4 to 17 out of every 100,000 people.^[3] It accounts for about 50 percent of all cases where people inherit both deafness and blindness from their parents.^[8] Among children who are deaf or hard of hearing, about 3 to 6 percent have Usher’s syndrome.^[8]

• Inner ear (cochlea)
• Retina
• Vestibular system

Types of Usher’s syndrome

There are three main types of Usher’s syndrome, and each type causes a different mix of health problems that appear at different ages.^[1] Scientists have identified at least 9 to 11 different genes that can cause Usher’s syndrome, which has led to multiple subtypes within each main type.^[1][7]

Type 1

People with type 1 Usher’s syndrome have the most severe symptoms from the earliest age. They experience profound hearing loss or complete deafness from birth, meaning they can only hear very loud sounds or no sounds at all.^[1] Balance problems are present from birth because the inner ear structures that help maintain balance don’t develop properly. These balance issues can make it harder for babies to sit up on their own and for children to learn to walk.^[1]

Vision problems typically start in early childhood, usually by age 10. Children first notice difficulty seeing in the dark, and their vision continues to worsen over time, often leading to severe vision loss by middle age.^[1] Type 1 is more common among people of Ashkenazi Jewish ancestry (from central and eastern Europe) and in French-Acadian populations.^[6]

Type 2

Type 2 is one of the most common forms of Usher’s syndrome.^[1] People with this type are born with moderate to severe hearing loss in early childhood, but their hearing typically doesn’t get worse over time.^[6] The hearing loss mainly affects their ability to hear high-pitched sounds, such as soft speech sounds like the letters “d” and “t.”^[3]

Unlike type 1, people with type 2 do not have balance problems and develop motor skills like walking at the expected age.^[1] Vision loss typically begins during the teenage years or early adulthood and progresses more slowly than in type 1.^[1] Many people with type 2 retain some central vision throughout their lives.

Type 3

Type 3 is the rarest form of Usher’s syndrome, accounting for only about 2 percent of all cases overall.^[3] However, it occurs more frequently in Finnish populations, where it accounts for about 40 percent of cases, and among people of Ashkenazi Jewish heritage.^[3]

People with type 3 are usually born with normal hearing and vision. Hearing loss typically begins during late childhood or the teenage years, after the child has already learned to speak, and becomes more severe over time.^[3] By middle age, most people with type 3 have profound hearing loss. Vision loss caused by retinitis pigmentosa also develops in late childhood or during the teenage years. About half of people with type 3 develop balance problems.^[3]

Symptoms

The main symptoms of Usher’s syndrome are hearing loss and vision loss, but the specific symptoms and when they appear depend on which type a person has.^[1] All people with Usher’s syndrome eventually develop retinitis pigmentosa, which affects their vision.

Hearing loss

Hearing loss in Usher’s syndrome is called sensorineural, which means it is caused by problems in the inner ear.^[3] The hearing loss happens because genetic changes affect nerve cells in the cochlea, the sound-transmitting structure of the inner ear, so these cells don’t send sound signals properly.^[2][4]

Some children with Usher’s syndrome are born completely deaf or with severe hearing loss. Others experience moderate hearing loss that may start later in childhood or adolescence.^[8] About 30 percent of people with retinitis pigmentosa report some degree of hearing loss, and about half of them are diagnosed with Usher’s syndrome.^[4]

Vision loss

Vision loss in Usher’s syndrome is caused by retinitis pigmentosa, which affects the retina—the light-sensitive tissue at the back of the eye.^[1] The retina contains special cells called rods and cones that convert light into electrical signals that the brain interprets as vision.^[4] In Usher’s syndrome, genes that make up retina cells change or mutate, causing these light-sensing cells to gradually break down.^[2]

The first sign of retinitis pigmentosa is usually difficulty seeing in low light or darkness, called night blindness.^[4] Children may have trouble moving around in the dark, take longer to adjust when lighting changes, or trip over objects they can’t see.^[1] As the condition progresses, people develop blind spots in their side vision (peripheral vision). Over time, these blind spots grow larger and merge together, creating what is called tunnel vision—where only the central area of vision remains.^[3]

Sometimes, clouding of the lens of the eye (cataracts) or cysts in the central part of the retina called the macula can cause additional vision problems and an earlier decline in central vision.^[8] In adults, retinitis pigmentosa can make it difficult to do daily activities like walking, driving, and reading.^[1]

Balance problems

Balance problems occur mainly in type 1 Usher’s syndrome and affect about half of people with type 3.^[2] These problems are caused by abnormal development of the vestibular system, which is the part of the inner ear that helps maintain the body’s balance and sense of position in space.^[3] The vestibular system contains special sensory cells called vestibular hair cells that detect gravity and head movement.^[8]

Children with balance issues may take longer than usual to sit up independently, begin walking later than expected, and may have difficulty riding a bicycle or playing certain sports.^[3]

What causes Usher’s syndrome?

Usher’s syndrome is caused by changes (mutations) in specific genes that are inherited from both parents.^[1] Scientists have found at least 9 to 11 different genes that can cause Usher’s syndrome.^[1][3] For type 1, at least six genes can cause the condition, with mutations in the MYO7A gene being most common, followed by mutations in the CDH23 gene.^[3] Type 2 can result from mutations in three genes, with USH2A gene mutations accounting for most cases.^[3]

These genes play important roles in the development and function of structures in both the inner ear and the retina. In the inner ear, they help maintain structures called stereocilia—tiny hair-like projections on sensory cells that transmit sound and motion signals to the brain.^[6] They also help maintain the structure and function of rod and cone cells in the retina, as well as supporting cells called the retinal pigmented epithelium.^[6]

How the condition is inherited

Usher’s syndrome is inherited in an autosomal recessive pattern.^[3] “Autosomal” means that men and women are equally likely to have the disorder and equally likely to pass it on to a child of either sex. “Recessive” means that a child must receive a changed gene from both biological parents to develop the condition.^[8]

When both parents are carriers—meaning they each have one normal gene and one changed gene—they typically don’t have symptoms themselves. With each pregnancy, they have a 25 percent chance of having a child with Usher’s syndrome, a 50 percent chance of having a child who is a carrier like them, and a 25 percent chance of having a child with two normal genes.^[5]

Because there are many different genetic versions of Usher’s syndrome, families rarely have a history of the condition. Parents are often surprised by the diagnosis because it doesn’t appear to run in their family.^[5] Estimates suggest that 1 in 10 people carries some form of a gene that can cause Usher’s syndrome, but the chance of two specific carriers meeting and having children together is small.^[5]

How is Usher’s syndrome diagnosed?

Doctors diagnose Usher’s syndrome by asking questions about medical history and testing hearing, balance, and vision.^[1] Because newborn hearing screening has reduced the age at which children with hearing loss are identified—from 12 to 18 months down to 6 months or less—audiologists (hearing specialists) are often the first healthcare professionals to work with families.^[5] However, the diagnosis of Usher’s syndrome, with its vision loss component, typically comes 5 to 10 years after the hearing loss is identified.^[5]

Eye examination

An eye doctor can check for retinitis pigmentosa as part of a comprehensive dilated eye exam.^[1] During this simple and painless exam, the doctor gives eye drops to dilate (widen) the pupils and then examines the eyes for retinitis pigmentosa and other eye problems. The exam includes a visual field test to check peripheral (side) vision.^[1]

Additional eye tests may include:

• Electroretinography (ERG): This test measures how well the retina responds to light.^[1]
• Optical coherence tomography (OCT): This test uses light waves to take a detailed picture of the retina.^[1]

Hearing and balance tests

Hearing tests measure the type and degree of hearing loss. Balance testing may include videonystagmography, which checks for abnormal eye movements that can indicate vestibular problems.^[1] These tests help doctors determine which type of Usher’s syndrome a person has, since hearing loss alone cannot indicate Usher’s syndrome or clearly differentiate between the types.^[5]

Genetic testing

Genetic testing can identify the specific gene mutations causing Usher’s syndrome.^[1] This testing is the only reliable way to determine the exact genetic type and subtype. While clinical testing can suggest which type of Usher’s syndrome a person has based on symptoms, DNA testing provides definitive answers.^[7] Understanding the genetic cause can help predict how the condition might progress and inform decisions about treatment options and family planning.

Treatment and management

There is currently no cure for Usher’s syndrome, but there are many ways to manage its effects on hearing, balance, and vision.^[1] The most effective approach involves early identification and intervention through tailored programs that consider the severity of hearing and vision loss, as well as the person’s age and abilities.^[11]

Managing hearing loss

Treatment for hearing loss may include:^[11]

• Hearing aids: These devices amplify sounds and can be helpful for people with moderate hearing loss.
• Cochlear implants: These electronic devices can provide sound signals directly to the auditory nerve for people with severe to profound hearing loss.
• Assistive listening devices: These tools help people hear better in specific situations, such as talking on the phone or watching television.
• American Sign Language: Learning sign language provides an important communication method.
• Speech therapy: This can help develop or maintain speech skills.

Managing balance difficulties

Balance problems can be addressed through:^[11]

• Physical and occupational therapy: These therapies help strengthen muscles, particularly core muscles, to improve balance.
• Orientation and mobility (O&M) training: This training teaches people how to move safely from one place to another and helps them use their remaining vision and other senses more effectively.^[11]

Managing vision loss

Treatment for vision loss may include:^[11]

• Low-vision services: An optometrist can provide training to use optical and electronic devices correctly, help people use their remaining vision more effectively, and suggest improvements to lighting and contrast in the home and workplace.
• Vision aids: Devices such as magnifiers, portable electronic magnifiers that reverse contrast (white text on black background), and special lenses can help with reading and other tasks.^[1]
• Braille instruction: Learning Braille provides an important method for reading as vision declines.
• Auditory training: This helps people learn to rely more on their hearing as vision decreases.

Vitamin A supplementation

A long-term clinical trial supported by the National Eye Institute found that a high dose of vitamin A may slow retinitis pigmentosa, though it cannot cure the condition.^[11] Researchers recommend that most adult patients with common forms of retinitis pigmentosa take a daily supplement of 15,000 IU (international units) of vitamin A under the supervision of their eye care professional. However, because patients with type 1 Usher’s syndrome did not participate in this study, high-dose vitamin A is not recommended for them.^[11]

Protective measures

Protecting remaining vision is important. Research shows the value of wearing sunglasses to protect eyes with retinitis pigmentosa from sun damage.^[16] Starting this habit young and encouraging consistent use can help preserve vision longer.

Living with Usher’s syndrome

Living with Usher’s syndrome involves ongoing adjustments to accommodate changes in hearing, vision, and sometimes balance. The psychological impact of living with progressive sensory loss can be significant, as people must constantly adapt to what is changing while trying to maintain independence and quality of life.^[18]

Emotional and psychological support

Getting an Usher’s syndrome diagnosis isn’t a single moment—it’s a process that unfolds over time.^[18] The reality of the condition often reveals itself gradually through everyday challenges: struggling to read a menu in a dim restaurant, hesitating at a busy crosswalk, or missing parts of conversations in noisy rooms. Grief doesn’t just come after loss—it comes with it, even when a person is still functioning and showing up in daily life.^[18]

Many people experience prejudice, as others may not understand that vision and hearing loss are invisible disabilities. People with Usher’s syndrome sometimes report being treated as second-class citizens, with others talking to their helpers rather than directly to them.^[19] Mental health support, counseling, and connecting with others who have similar experiences can help people navigate these challenges.

Practical adjustments at home

Making modifications at home can improve safety and independence:^[16]

• Keep spaces free of clutter, especially on floors, since decreased peripheral vision makes it harder to see objects beside or below.
• Install nightlights throughout the home, particularly in hallways and rooms without natural light.
• Use rope lights along hallway floors to mark common pathways, similar to lights in movie theater aisles.
• Ensure good lighting in all areas, but avoid harsh glare that can make vision worse.
• Use contrasting colors to help objects stand out—for example, placing light-colored objects on dark surfaces.
• Consider wearing a flashlight headlamp for tasks in low-light conditions.

Education and career planning

Early identification allows educational programs to begin as soon as possible, preparing individuals for employment and independent living.^[12] Programs should be tailored to each person’s specific needs, taking into account the type and severity of their hearing and vision loss, their age, and their individual strengths.

Support services

Support Service Providers (SSPs) are professionals trained to work with people who have combined vision and hearing loss.^[17] They provide environmental information so that the person can make informed decisions or participate more fully in activities without having to rely only on friends or family. SSPs may assist with reading bills, shopping, participating in social activities, and attending family events. Some states offer free SSP services.

Connection and community

Connecting with others in the Usher’s syndrome community can provide valuable support, information, and understanding. Many people find that sharing experiences with others who face similar challenges helps reduce feelings of isolation and provides practical strategies for daily living.

Current research

Research into effective treatments for Usher’s syndrome is actively progressing in several areas, including gene therapy, stem cell therapy, drug-based treatments, and retinal implants.^[14]

Gene therapy

Gene therapy approaches aim to correct or replace the faulty genes that cause Usher’s syndrome. AAVantgarde Bio has moved a dual-vector gene therapy for Usher syndrome type 1B (caused by mutations in the MYO7A gene) into a Phase 1/2 clinical trial.^[13] This represents an important step toward developing treatments that address the underlying genetic cause of the condition.

RNA-based therapies

Sepul Bio is advancing RNA therapies (antisense oligonucleotides) for specific genetic mutations. The company has launched clinical trials for ultevursen, designed for people with exon 13 mutations in the USH2A gene—a common cause of type 2 Usher’s syndrome.^[13] These therapies work by targeting the genetic instructions that cells use to make proteins, potentially correcting the effects of specific mutations.

Drug therapies

Nacuity has reported promising results from a Phase 2 clinical trial of NACA, an oral antioxidant therapy for Usher’s syndrome. The trial found that NACA reduced the loss of light-sensing cells in the retina by 50 percent.^[13] This type of treatment aims to protect retinal cells from damage caused by oxidative stress, potentially slowing vision loss.

Research is also exploring whether certain drugs can counteract specific types of genetic mutations called nonsense mutations, which occur in a subset of people with Usher’s syndrome.^[14]

Retinal implants

Scientists are developing artificial retinas—electronic devices that can provide some visual perception for people who have lost most of their vision.^[14] These implants work similarly to cochlear implants, using a small camera mounted on glasses that sends signals to electrodes placed in or near the retina. While these devices don’t restore normal vision, they can help people perceive light, shapes, and movement, improving their ability to navigate their environment.

The ongoing research offers hope that treatments to slow or prevent the progression of Usher’s syndrome may become available in the future. People with Usher’s syndrome and their families are encouraged to stay informed about research developments and consider participating in clinical trials when appropriate.