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Author: Jack Slemenda Converse College, SC Date submitted to deafed.net – March 20, 2008 To contact the author for permission to use this PowerPoint, please e-mail: [email protected] To use this PowerPoint presentation in its entirety, please give credit to the author. Usher’s Syndrome Jack Slemenda Converse College USHER’S SYNDROME Usher’s Syndrome is an inherited condition that causes 1) a serious hearing loss that is usually present at birth or shortly thereafter and 2) progressive vision loss caused by retinitis pigmentosa (RP). RP is a group of inherited diseases that cause night-blindness and peripheral (side) vision loss through the progressive degeneration of the retina, the light-sensitive tissue at the back of the eye that is crucial for vision. Who is affected by Usher’s Syndrome? Approximately 3-6 percent of all deaf children and perhaps another 3-6 percent of hard-of-hearing children have Usher Syndrome. In developed countries such as the United States, about 4 babies in every 100,000 births have Usher’s Syndrome. What causes Usher’s Syndrome? Usher’s Syndrome is inherited or passed from parents to their children through genes. Some genes specify traits such as hair color. Other genes are involved in the development of body parts, such as the ear. Still others determine how parts of the body work. Each person inherits two copies of each gene, one from each parent. Additional Causes of Usher’s Syndrome Genes for Usher’s Syndrome are autosomal recessive, a term meaning that 1) Usher genes are located on chromosomes other than the sex chromosomes, and 2) both parents must contribute the mutated gene to the child before the disorder is seen. A number of different genes have been found to cause the various types of Usher’s Syndrome How is Usher’s Syndrome diagnosed? Since Usher’s Syndrome involves both hearing and visual symptoms; testing is performed on both. Visual function tests: visual fields and electroretinogram (ERG) A retinal examination Hearing tests Balance tests for all patients age ten years and older What are the types of Usher’s Syndrome? Type 1 (USH1) Type 2 (USH2) Type 3 (USH3) Together, they account for approximately 90-95 percent of all cases of children who have Usher’s Syndrome Characteristics of the three types of Usher’s Syndrome? Type 1 Profoundly deaf from birth Have severe balance problems. Because of the balance problems, children with USH1 are slow to sit without support and rarely learn to walk before they are 18 months old. Little or no benefit from hearing aids. Most use sign language as their primary means of communication. Usually begin to develop vision problems by the time they are ten. Visual problems most often begin with difficulty seeing at night, but tend to progress rapidly until the individual is completely blind. Characteristics of Usher’s Syndrome Type 2 Born with moderate to severe hearing impairment and normal balance. Use speech to communicate. Visual problems progress more slowly. Characterized by blind spots that begin to appear shortly after the teenage years. When an individual's vision deteriorates to blindness, his or her ability to speech read is lost. Characteristics of Usher’s Syndrome Type 3 Normal hearing and normal to near-normal balance. Hearing worsens over time Children develop noticeable hearing problems by their teenage years and usually become deaf by mid- to late adulthood. Night blindness usually begins sometime during puberty. Blind spots appear by the late teenage years to early adulthood. By mid-adulthood, the individual is usually blind. How is Usher’s Syndrome treated? There is no cure for Usher’s Syndrome. The best treatment: early identification (by a Genetics Doctor) in order to begin educational programs. The nature of these educational programs will depend on the severity of the hearing and vision impairments as well as the age and abilities of the individual. Special training needs to incorporate the family, as well. Access to technology :hearing aids, assistive listening devices, or cochlear implants; orientation/ mobility training; and communication services and independent-living training that may include Braille instruction, low-vision services, or auditory training. Communication services and independent-living training that may include Braille instruction, low-vision services, or auditory training. Latest research findings June 12, 1998, issue of the journal Science, by Dr. William J. Kimberling, an investigator supported by the National Institute on Deafness and Other Communication Disorders (NIDCD). The scientists described three different mutations in a gene called USIIa. This gene was previously mapped to a location on chromosome 1 and is associated with the syndrome. In April 2003, NIDCD researchers, along with their research collaborators from universities in New York, N.Y., and Tel Aviv, Israel, pinpointed a mutation, named R245X, of the PCDH15 gene that accounts for a large percentage of USH1 cases in today's Ashkenazi Jewish population. Usher’s Syndrome is rare in the general population (3 per 100,000). However, two to 5 percent of the genetic deaf population have the disease. This inherited condition is the cause of more than half of all deaf-blindness in adults. Students need to be informed that they have Usher’s and also of the disabling conditions. Students visual field and dark adaptation abilities deteriorate so that they will need additional assistance during the evening hour www.visionsimulator.com Provisions for those with Usher’s Syndrome Family counseling Medical and Educational diagnoses Itinerant home services Teacher training Instruction: includes the use of other senses; augmentative devices; enlarged books, symbols and tactile objects.. RESOURCES Dorothy Stiefel’s book called The Madness of Ushers Syndrome: Copying with Vision and Hearing Loss/Usher’s Syndrome Type II. American Association of the Deaf-Blind (AADB) 814 Thayer Avenue, Suite 302 Silver Spring, MD, 20910 Voice: (301) 495-4403 TTY: (301) 495-4402 Fax: (301) 495-4404 E-mail: [email protected] Internet: www.aadb.org Additional Resources Better Hearing Institute (BHI) 515 King Street, Suite 420 Alexandria, VA, 22314 Toll-free Voice: (800) EAR-WELL (327-9355) Internet: www.betterhearing.org Helen Keller National Center for Deaf-Blind Youths and Adults (HKNC) 141 Middle Neck Road Sands Point, NY, 11050 Voice: (516) 944-8900 TTY: (516) 944-8637 Internet: www.hknc.org References Scheetz, Nanci A., (2001)Orientation to Deafness 2nd Edition . Library of Congress National Institute on Deafness and Other Communication Disorders National Institutes of Health 31 Center Drive, MSC 2320 Bethesda, MD USA 20892-2320 E-mail: [email protected] www.visionsimulator.com