Stargardt disease is the most common form of inherited juvenile macular degeneration. Progressive vision loss is caused by the death of photoreceptor cells in the central portion of the retina called the macula.
The first symptoms of Stargardt disease are usually noticed in childhood or early adulthood. These include difficulty reading and other problems with central vision; blind spots can occur, and these may increase in size over time.
Both eyes are usually affected in a similar manner and colour vision may be affected in the later stages of disease. The rate of progression and degree of visual loss can vary from person to person and even among affected members of the same family. It is therefore very difficult to predict what an individual’s vision will be like at a specific time in the future.
The majority of people with Stargardt disease have mutations in the ABCA4 gene and the condition is usually inherited in an autosomal recessive manner. For more information on inheritance patterns, visit Unlock Genetics on our website: www.RetinaUK.org.uk/unlock/discover-inheritance-patterns.
Faults in ABCA4 can lead to the build-up of a toxic waste product known as lipofuscin in the retinal pigment epithelium (RPE), which sits just behind the photoreceptors. This eventually leads to the death of cells in the central retina.
Rarely, Stargardt disease is caused by mutations in the ELOVL4 gene, which lead to the formation of ELOVL4 protein clumps that build up and interfere with retinal cell functions, ultimately leading to degeneration.
At present, there are no effective treatments for Stargardt disease but various approaches are being explored. Some of these are specific to certain genetic faults; it is important that people with Stargardt disease are offered genetic testing so that they can access future treatments and clinical trial participation.
Researchers funded by Retina UK are investigating the development of molecular “patches” to cover up and effectively “silence” faulty sections of the ABCA4 gene so that it can function normally. This potential treatment is not yet ready to be tested in humans, but we will report any updates in the Research News section of our website: https://retinauk.org.uk/category/research-news/.
Meanwhile, researchers at Southampton University are involved in an EU-funded clinical trial of a new drug called remofuscin that aims to remove toxic lipofuscin from the retina and therefore prevent further damage.
Further information on current clinical trials can be found at www.clinicaltrials.gov; you can also read about possible treatment approaches for retinal disease at https://retinauk.org.uk/research/approaches-to-treatment/.
In terms of day to day management, bright light can increase the accumulation of toxic lipofuscin in the retina so it is recommended that people living with Stargardt disease use good quality sunglasses when in direct sunlight. Taking extra vitamin A, such as in a vitamin supplement, may have a negative effect on the condition and should be avoided.
Retina UK is occasionally approached by researchers and companies looking for our help in recruiting participants for studies or patient involvement initiatives, and we can pass on details of opportunities to people on our database who have expressed an interest in these activities and given their consent to be contacted. Anyone who is not already in contact with Retina UK can call 01280 821334 or email info@RetinaUK.org.uk so that we can add them to our database. It is helpful for us to have as much detail about the diagnosis as possible, including genetic diagnosis if available, as some opportunities are condition specific. .
The Retina UK Helpline provides information, support and signposting to people affected by inherited sight loss as well as healthcare and education professionals.
Contact 0300 111 4000 (9.30am – 9.30pm Mon to Fri) or Helpline@RetinaUK.org.uk.