The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. This condition can also be inherited in an X-linked pattern. The genes associated with X-linked retinitis pigmentosa are located on the X chromosome, which is one of the two sex chromosomes. In males who have only one X chromosome , one altered copy of the gene in each cell is sufficient to cause the condition.
In females, who have two X chromosomes , mutations usually have to occur in both copes of the gene to cause the disorder. However, at least 20 percent of females who carry only one mutated copy of the gene develop retinal degeneration and associated vision loss.
In most cases, males experience more severe symptoms of the disorder than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. In 10 to 40 percent of all cases of retinitis pigmentosa, only one person in a family is affected. In these families, the disorder is described as simplex.
It can be difficult to determine the inheritance pattern of simplex cases because affected individuals may have no affected relatives or may be unaware of other family members with the disease.
Simplex cases can also result from a new gene mutation that is not present in other family members. Genetics Home Reference has merged with MedlinePlus. Learn more. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. Retinitis pigmentosa. By Kierstan Boyd. Edited By David Turbert.
In this article: What Is Retinitis Pigmentosa? What Causes Retinitis Pigmentosa? Can Retinitis Pigmentosa Be Treated? Related Ask an Ophthalmologist Answers What is the importance of fundoscopy? Will working long hours on the computer be a problem for someone with a hole in the retina? How long will the gas bubble stay in my eye after retinal detachment treatment?
Is pink vision normal after retinal surgery? In some cases, an affected person inherits the mutated gene from an affected parent. In other cases, the mutation occurs for the first time in a person with no family history of the condition. Autosomal recessive inheritance means that to be affected, a person must have a mutation in both copies of the responsible gene in each cell.
Affected people inherit one mutated copy of the gene from each parent, who is referred to as a carrier. Carriers of an autosomal recessive condition typically are unaffected.
Males have one X chromosome and one Y chromosome , while females have two X chromosomes. Males who have a mutation on their X chromosome will be affected, while female carriers of the mutation may be affected or unaffected, because they have another X chromosome with a normal copy of the gene.
All the daughters of an affected male will inherit the mutation; none of his sons will inherit the mutation. Diagnosis Diagnosis. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional. Orphanet lists international laboratories offering diagnostic testing for this condition. Treatment Treatment.
Available treatments aim to slow the progression of the disease and primarily include light avoidance and the use of low-vision aids. Some practitioners also consider vitamin A as a possible treatment option. However, taking too much vitamin A can be toxic and the effects of vitamin A on the disease appear to be relatively weak.
While DHA is known to play a structural role in retinal cells , more research is needed to determine whether supplements should be recommended. Stem cell transplantation would involve the injection and integration of stem cells into the retina, in hopes these cells will replace dead cells and provide the missing enzymes and chemicals needed for sight.
Gene therapy could potentially be used when the disease-causing mutation is known and would aim to restore production of the missing or abnormal protein. Studies with retinal prosthetics have tested devices that transform light into electrical signals that can be sent directly to the inner retina and brain, avoiding the diseased part of the outer retina. Though challenges remain, preliminary research into these technologies has been promising.
Voretigene neparvovec-rzyl Brand name: Luxturna - Manufactured by Spark Therapeutics, Inc FDA-approved indication: An adeno-associated virus vector -based gene therapy indicated for the treatment of patients with confirmed biallelic RPE65 mutation-associated retinal dystrophy. Patients must have viable retinal cells determined by a treating physician. Statistics Statistics. The prevalence of retinitis pigmentosa in the United States is estimated to be between 1 in 3, to 1 in 4, individuals.
Do you have updated information on this disease? Find a Specialist Find a Specialist. Healthcare Resources To find a medical professional who specializes in genetics, you can ask your doctor for a referral or you can search for one yourself. You can also learn more about genetic consultations from MedlinePlus Genetics. Related Diseases Related Diseases. Conditions with similar signs and symptoms from Orphanet.
Besides non syndromic forms, there are syndromic forms of RP of which the most frequent are Usher syndrome RP and deafness and BardetBiedl syndrome RP and metabolic impairment. RP is to be distinguished from macular dystrophies peripheral visual field is normal and Leber congenital amaurosis congenital retinal dystrophy see these terms.
Visit the Orphanet disease page for more information. Research Research. Clinical Research Resources ClinicalTrials. Click on the link to go to ClinicalTrials. Please note: Studies listed on the ClinicalTrials. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study. Orphanet lists European clinical trials, research studies, and patient registries enrolling people with this condition.
Organizations Organizations. Organizations Supporting this Disease. Curing Retinal Blindness Foundation E-mail: kim crb1. Organizations Providing General Support. Do you know of an organization? Learn More Learn More. Where to Start MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic. This website is maintained by the National Library of Medicine.
Usher syndrome is a genetic disorder that includes retinitis pigmentosa and a partial or total hearing loss from birth. Usher syndrome is categorised into three broad groups according to the type and severity of symptoms. Type 1 and Type 2 account for around 10 per cent of children who are born deaf. This page has been produced in consultation with and approved by:. Blepharospasm means involuntary twitching, blinking, closure or squeezing of the eyelids.
Braille is a reading and writing system for blind and vision impaired people, made up of raised dots that can be? A cataract of the eye is like the lens of a camera becoming fogged up. People who are colourblind usually have difficulty with the colours green, yellow, orange and red. Conjunctivitis is an eye infection caused by a bacteria or virus. Symptoms include eye redness, a discharge and swollen lids.
Conjunctivitis is treated with antibacterial eye drops or ointment. Children must not attend school or child care if they have conjunctivitis. Content on this website is provided for information purposes only. Information about a therapy, service, product or treatment does not in any way endorse or support such therapy, service, product or treatment and is not intended to replace advice from your doctor or other registered health professional. The information and materials contained on this website are not intended to constitute a comprehensive guide concerning all aspects of the therapy, product or treatment described on the website.
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Skip to main content. Home Eyes. Eyes - retinitis pigmentosa. Actions for this page Listen Print. Summary Read the full fact sheet. On this page. Rods and cones explained Symptoms of retinitis pigmentosa RP Tunnel vision Cataracts Types of retinitis pigmentosa Diagnosis of retinitis pigmentosa Treatment for retinitis pigmentosa Research into retinitis pigmentosa Gene therapy research Transplant research Retinal prosthesis Management of retinitis pigmentosa Progression of retinitis pigmentosa Usher syndrome Where to get help.
Rods and cones explained The retina contains millions of cells called rods and cones. Symptoms of retinitis pigmentosa RP Since retinitis pigmentosa is a progressive condition, the symptoms and signs worsen as time goes by.
Early symptoms can include: poor night vision problems seeing things in dimly lit environments loss of peripheral side vision difficulty in judging changes in peripheral vision, such as curbs or steps. Tunnel vision One of the first symptoms of RP is night blindness, followed by the loss of peripheral vision.
In other cases of RP, the central area of the retina is affected first, which means the person may have trouble with: distinguishing colours reading recognising visual details.
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