If just one changed Usher gene is inherited, the child won’t develop the condition, but will be a carrier. This means that for a child to develop Usher syndrome, they must inherit the same Usher gene change from both their mother and their father. Usher syndrome follows an autosomal recessive inheritance pattern. Researchers believe there are about 15 genes that can cause Usher syndrome. The different types of Usher syndrome are caused by changes in different genes. These genes also come in pairs – one from each parent. The estimated 30,000 to 40,000 genes are beaded along these tightly bundled strands. Humans have 46 paired chromosomes, with two sex chromosomes that decide gender and 44 chromosomes that dictate other factors. Most people with US3 are of Finnish descent. Balance deteriorates as the person gets older.Vision loss starts to develop during the teenage years and may progress during life.Measurable hearing loss occurs by puberty.The loss of hearing becomes more pronounced as the person gets older.The person is born with normal hearing and close to normal balance.Only one subtype of US3 has been discovered to date. Vision loss, such as blind spots, starts to develop during the teenage years and may progress during life.Balance may be affected in later years.Severe loss of hearing is experienced in the higher sound frequency range.Moderate loss of hearing is experienced in the lower sound frequency range.Vision loss varies with each person, but often develops in the first ten years of life.Eye problems vary with each person, but may start to develop at around ten years of age.Balance may be affected and children are often late to sit, stand and walk.Other means of communication, like sign language (Auslan), are needed.The person is profoundly deaf from birth.Each type is further divided into subtypes. These groups are called Type 1, Type 2 and Type 3. Usher syndrome is categorised into three broad groups according to the type and severity of symptoms. proprioception system – special receptors in our muscles, joints and skin that sense the movement and position of the joints.When the head moves, the movement of the fluid tells the brain exactly how far, how fast and in what direction the head is moving, by relaying the information down the vestibular nerve vestibular system – a series of fluid-filled canals within the ear, set at different angles.This is because our ability to balance relies on information being sent to our brain from our: balance problems – can occur due to vision and inner ear impairments.Over time, their field of vision becomes smaller until they only have a ‘tunnel’ of central vision At first, a person with RP becomes ‘night blind’, meaning that they can no longer see in dim light. RP is a form of eye disease that results in the gradual loss of vision over time, due to deterioration of the retina. vision impairment leading to blindness – in Usher syndrome this is caused by retinitis pigmentosa (RP).The symptoms and signs of Usher syndrome depend on the type, but generally include: Services aim to help the person and their family prepare for and cope with their vision and hearing loss. There is currently no cure for Usher syndrome. Type 1 and Type 2 account for approximately five per cent of all children born with a hearing impairment. Usher syndrome is categorised into three broad groups according to the type and severity of symptoms – Types 1, 2 and 3. Some people with Usher syndrome also experience problems with their balance. People with Usher syndrome often have partial or total hearing loss and a gradual vision loss caused by retinitis pigmentosa. It is the most common genetic cause of combined vision and hearing impairment and deafblindness.
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