Genetic testing - usually through a simple blood test - is the only way to definitively diagnose Usher syndrome. Prior to genetic testing, a diagnosis wasn’t usually made until one's 20s, 30s or 40s, when the vision loss from RP became severe enough to affect communication, socialization, daily living, and travel. With the availability of genetic testing, Usher syndrome can be diagnosed in infancy. Balance problems can become more pronounced as visual fields decrease. The result is that they learn to sit up and walk later than their peers. Balance issues manifest early in children with Usher type 1. These symptoms will generally be noticed before the age of 10 and continue through adulthood.Ĭhildren and adults with Usher type 1 usually have vestibular issues that affect balance. The symptoms of RP first manifest as difficulty seeing in dimly lit areas - or night blindness - and a gradual loss of peripheral vision (tunnel vision). There are five subtypes of Usher 1: type 1B, type 1C, type 1D, type 1F and type 1G.Ĭhildren with Usher type 1 are usually born profoundly deaf and experience progressive vision loss due to a retinal disease called retinitis pigmentosa (RP). This means that a child receives two copies of the same Usher 1 gene, one from each parent. Usher syndrome type 1 is a recessive genetic disease. (For an overview of the science behind Usher syndrome type 1, review this article from the National Institutes of Health (NIH) National Center for Biotechnology Information (NCBI), last revised October 8, 2020.) Recent breakthroughs in genetic testing are allowing for earlier diagnosis of all types of Usher syndrome. DNA testing - usually with a simple blood test - is the only reliable way of determining the true genetic type. There are six different genes that cause Usher type 1, three that cause Usher type 2, and two that cause Usher type 3. There are at least eleven different genetic types of Usher syndrome. Some with type 3 also experience balance problems. Hearing can deteriorate steadily over ten or fifteen years. Children usually have normal hearing and vision at birth, then develop hearing loss and RP in adolescence or later. It occurs with higher frequency in individuals of Ashkenazi Jewish and Finnish heritage. Type 3 – is the rarest form of Usher syndrome. Balance is not affected, therefore children with type 2 walk at the typical age of 10 to 14 months. Speech assisted by the use of lip-reading and hearing aids or cochlear implants will usually be their primary method of communication. RP may not become apparent until adolescence. Many adults with Usher 1 communicate with sign language and identify as a culturally Deaf and/or DeafBlind. Children with Usher type 1 who receive cochlear implants at an early age usually communicate using speech and lip-reading. Poor balance from birth is often associated with Usher type 1, which causes delays in sitting and walking. Type 1 – causes profound deafness, Vision loss cause by retinitis pigmentosa (RP) may be noticed before the age of 10. There are three clinical types of Usher Syndrome:
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