These substances form after phototransduction, the process by which light entering the eye is converted into electrical signals that are transmitted to the brain. These toxic substances build up and form lipofuscin in the photoreceptor cells and the surrounding cells of the retina, eventually causing cell death. Loss of cells in the retina causes the progressive vision loss characteristic of Stargardt macular degeneration.
The ELOVL4 protein is primarily active expressed in the retina, but is also expressed in the brain and skin. The function of very long-chain fatty acids within the retina is unknown. When mutations in the ABCA4 gene cause this condition, it is inherited in an autosomal recessive pattern , which means both copies of the gene in each cell have mutations.
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. When this condition is caused by mutations in the ELOVL4 gene, it is inherited in an autosomal dominant pattern , which means one copy of the altered gene in each cell is sufficient to cause the disorder.
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. An eye healthcare provider will do various eye tests, photographs and scans of your eyes.
This helps better understand your eye problem. Often you will be asked about your general health and if anyone else in the family might have vision problems. Your doctor may recommend you visit a genetic eye clinic for genetic counselling. This may help you:. During your appointment genetic testing may be suggested.
This involves having a small blood or saliva sample collected and sent to a laboratory. If you live in another state, it is best to speak with your eye healthcare provider and local clinical genetic service.
Currently, there may be a possible treatment for a very rare inherited retinal disease caused by a specific gene. But for most inherited retinal diseases, there is no potential medicine, surgery or ability to cure vision loss. There is a lot of promising research into gene therapy and stem cell technology and upcoming clinical trials that are bringing hope to families. Inherited retinal diseases are a broad group of genetic eye conditions that cause vision loss and sometimes, legal blindness.
They can occur from birth through to late adulthood. Close Close. Eye conditions. Abnormal patterns of light response suggest the presence of Stargardt disease or other diseases that involve retinal degeneration. OCT is a scanning device that works a little like ultrasound.
Ultrasound captures images by bouncing sound waves off living tissues; OCT does this with light waves. The patient places his or her head on a chin rest and invisible, near-infrared light is focused on the retina. Cross-sectional pictures of the retina are analysed for any abnormalities which could indicate retinal degeneration. OCT is sometimes combined with infrared scanning laser ophthalmoscopy ISLO to provide additional surface images of the retina.
A specific pattern of autofluorescence imaging may be seen in patients with Stargardt disease. As part of the diagnosis, the patient may be invited to take a genetic test to learn more about their particular condition, and enable research scientists to learn more about the condition in general. Patients are not obliged to take a genetic test, but some people find it helpful to know more.
Some patients may find it helpful to talk with a genetic counsellor first. Usually part of the research team, the genetic counsellor will help a patient and their family understand how the condition has been inherited, and the implications for other family members and future generations.
They will enable the patient to make informed decisions about testing and support them through the process. The consultant will be able to provide more information about genetic testing. Being diagnosed can be stressful and highly emotional. Some patients benefit from working with a professional counsellor to understand their situation and find ways to manage their feelings.
Our free telephone counselling service is provided by accredited counsellors who have extensive experience of working with people with sight loss. Please call for a referral.
Children with sight loss are eligible for special educational needs SEN support in school. This can provide your child with the adaptations, equipment and support they need to fully access the curriculum. There is currently no treatment for Stargardt disease. However, there is a wide range of support available to help people with the condition, as well as their family and friends. If you or anyone in your family experiences any sudden changes in vision seek urgent medical advice from an eye hospital.
There is a great deal of research going on into potential treatments. We are finding out more about genetics, and gene-based therapies are being developed.
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