![]() ![]() If both parents are carriers of a mutated gene for Usher syndrome, they will have a one-in-four chance of having a child with Usher syndrome with each birth. People with a mutation in a gene that can cause an autosomal recessive disorder are called carriers, because they “carry” the gene with a mutation, but show no symptoms of the disorder. If a child has a mutation in one Usher syndrome gene but the other gene is normal, he or she is predicted to have normal vision and hearing. The word recessive means that, to have Usher syndrome, a person must receive a mutated form of the Usher syndrome gene from each parent. The term autosomal means that the mutated gene is not located on either of the chromosomes that determine a person’s sex in other words, both males and females can have the disorder and can pass it along to a child. Usher syndrome is inherited as an autosomal recessive trait. Mutated genes may cause cells to act differently than expected. Every person inherits two copies of each gene, one from each parent. Genes contain instructions that tell cells what to do. Genes are located in almost every cell of the body. Usher syndrome is inherited, which means that it is passed from parents to their children through genes. In developed countries such as the United States, about four babies in every 100,000 births have Usher syndrome. 1-in-4 chance of having a child who neither has Usher syndrome nor is a carrierĬhances of Inheriting a Recessive DisorderĪpproximately 3 to 6 percent of all children who are deaf and another 3 to 6 percent of children who are hard-of-hearing have Usher syndrome.2-in-4 chance of having a child who is a carrier. ![]() 1-in-4 chance of having a child with Usher syndrome.When two carriers of the same Usher syndrome gene have a child together, with each birth there is a: has inherited a change in the same gene from each parentĪn individual who has one changed Usher syndrome gene is called a carrier.a person with one changed gene does not have the disorder, but can pass either the changed or the unchanged gene on to his or her childĪn individual with Usher syndrome usually:.a person must inherit a change in the same gene from each parent in order to have the disorder.Genetic disorders are inherited in different ways. Every individual has two copies of the same gene. Genetic disorders can be caused by a change(s) in a gene. Chances of Inheriting a Recessive Disorder The optic nerve (arrow) looks very pale, the vessels (stars) are very thin and there is characteristic pigment, called bone spicules (double arrows). Photograph of the retina of a patient with Usher syndrome (left) compared to a normal retina (right). Together, they account for approximately 90 to 95 percent of all cases of children who have Usher syndrome. In the United States, types 1 and 2 are the most common types. There are three clinical types of Usher syndrome: type 1, type 2, and type 3. Many people with Usher syndrome also have severe balance problems. As RP progresses, the field of vision narrows-a condition known as “tunnel vision”-until only central vision (the ability to see straight ahead) remains. The retina is a light-sensitive tissue at the back of the eye and is crucial for vision. RP causes night-blindness and a loss of peripheral vision (side vision) through the progressive degeneration of the retina. The major symptoms of Usher syndrome are hearing loss and an eye disorder called retinitis pigmentosa, or RP. A syndrome is a disease or disorder that has more than one feature or symptom. Usher syndrome is the most common condition that affects both hearing and vision. ![]()
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