what is usher syndrome?
Usher syndrome is a genetic condition characterised by hearing loss or deafness, the progressive loss of vision and in some cases, vestibular dysfunction. The loss of vision is caused by an eye disease called Retinitis Pigmentosa (RP), which affects the light sensitive area of tissue on the back of the eye (the retina).
Usher Kids UK has produced this leaflet which gives basic information about Usher syndrome. This may be helpful in providing wider family members or professionals supporting a child with Usher syndrome with an understanding of the condition. Hard copies of this leaflet can be requested - just email info@usherkidsuk.com
Usher Types:
There are three main types of Usher syndrome - Type 1, Type 2 and Type 3. Each of these types has a number of different genes responsible for causing the syndrome.
Type 1:
Type 2:
Type 3:
There are three main types of Usher syndrome - Type 1, Type 2 and Type 3. Each of these types has a number of different genes responsible for causing the syndrome.
Type 1:
- Type 1 is comprised of 5 different subtypes; 1B, 1C, 1D, 1F and 1G depending on the specific gene mutation.
- Children diagnosed with Usher syndrome type 1 are profoundly deaf at birth and have a dysfunctional vestibular system.
- Due to the vestibular dysfunction, a child with Usher syndrome type 1 will usually take longer to sit up and develop walking at a later stage than a typically developing child.
- Gradual vision loss in the child occurs due to Retinitis Pigmentosa (RP). The severity and onset of RP varies between individuals but commonly develops before the age of 10. Vision problems are initially characterised by night blindness or tunnel vision but this also varies between individuals.
Type 2:
- Usher syndrome type 2 can be grouped into 3 subtypes, 2A, 2C and 2D.
- In Usher syndrome type 2, the severity of hearing loss from birth can range from very mild to severe. Those with Usher syndrome type 2 do not have a dysfunctional vestibular system.
- Vision loss due to the RP does not usually develop until late adolescence or in some cases until the late twenties.
Type 3:
- Usher syndrome type 3 is very rare compared to the other Usher syndrome types and only one subtype has been discovered so far, with the majority of people with USH3 living in Finland.
- A person with Usher syndrome type 3 is born with normal hearing and close to normal balance, however hearing gradually deteriorates with age.
- A measurable hearing loss usually occurs by puberty and vision starts to deteriorate during the teenage years and may progress during life.
