What is Stargardt’s disease?
Stargardt’s disease is a type of macula dystrophy grouped under inherited retinal disease. It may also be called juvenile macular degeneration.
For normal vision, the retina acts like the film in a traditional camera. It is here where the pictures are created, then sent to the brain for interpretation.
The retina is the light-sensitive tissue at the back of the eye. Stargardt’s disease affects the most sensitive part of the central retina called the macula. This is where your sharp vision occurs.
How common is Stargardt’s disease?
Stargardt’s disease is a type of inherited retinal disease. Altogether, inherited retinal diseases affect around 1 in 4000 people or over 2 million people worldwide. They are the leading cause of blindness in working age adults.
What are the causes?
Stargardt’s disease is a genetic condition.
Genes contain DNA, which is short for ‘deoxyribonucleic acid’. A gene has the instructions on how retina cells in our body grow and work.
Stargardt’s disease is caused by a change or ‘mistake’ in one or more genes. Therefore, cells in the retina don’t work as they are supposed to and over time you lose vision.
Stargardt’s disease is often caused by changes in the ABCA4 gene. In most people there is a low chance that an affected parent with Stargardt’s disease will pass the condition to their children. Parents who are closely related (e.g. cousins) may have a higher chance than unrelated parents to both carry the same ABCA4 gene causing Staragart’s.
For a small number of families, the condition is linked with a change in the ELOV4 gene. There is a chance this may be passed onto children.
There may be many more genes that cause Stargardt’s, but they haven’t been discovered yet.
Each family circumstance is different. Therefore, it is recommended you seek genetic counselling for your specific type of Stargardt’s Disease. This will provide you the most accurate information and best care possible.
What are the symptoms?
A decline in central vision is usually the first symptom of Stargardt’s disease. You may have trouble reading, recognising faces or watching TV.
Other symptoms may include:
- blurred vision
- a central blind spot
- colour blindness
- sensitivity to light
- difficulty adapting from light to dark settings.
Stargardt’s disease usually appears in childhood and young adulthood. But in some people it may develop later in life.
The way symptoms progress in Stargardt’s disease is different for each person.
It is uncommon for someone with the condition to go completely blind.
How is Stargardt’s disease diagnosed?
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:
- understand what Stargardt’s disease could mean for you
- provide support to help you adjust to living with or being at risk of developing the condition
- talk about whether children or family members are likely to develop Stargardt’s disease
- if you are thinking about starting a family
- learn about any appropriate research studies or clinical trials.
Sometimes doctors cannot be certain which gene is causing Stargardt’s disease just by looking into the eye. During your appointment genetic testing may be suggested. This involves having a small blood or saliva sample collected and sent to a laboratory. Genetic testing could help find out the exact gene causing your type of Stargardt’s disease. However, it doesn’t always identify the gene because many genes are still being discovered.
In Victoria, you can access specific genetic eye counselling through the Ocular Genetics Clinic at the Royal Victorian Eye and Ear Hospital or Genetic Eye Clinic at The Royal Children’s Hospital. If you live in another state, it is best to speak with your eye healthcare provider and local clinical genetic service.
What treatment is available?
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.
There are steps you can take to look after and maximise your vision. These include:
- regular eye checks, no matter the level of your vision
- orientation and mobility training
- using low vision aids such as magnifiers and closed-circuit televisions
- using technology and applications (apps) on your devices
- educational support for students at school or university
- wearing sunglasses
- extra lighting if you need help in dark environments
- not smoking
- having a healthy diet.
You may find support groups and online patient communities helpful. Read stories of people living with Stargardt’s disease.
What research is happening at CERA?
CERA researchers are working on potential treatments for inherited retinal diseases, like Stargardt’s disease. At the same time, they’re advancing scientific knowledge of the genes that cause these conditions.
- Principal Investigator Dr Tom Edwards is investigating a gene therapy for a specific inherited retinal disease.
- Professor Alex Hewitt (CERA) and Professor Alice Pébay (University of Melbourne) are using stem cell technology and gene-editing techniques to develop new treatments.
- Dr Raymond Wong is using cell reprogramming and stem cell technologies to understand how to replace lost retinal cells.
- CERA and the University of Melbourne are creating a national clinical database of people with inherited retinal diseases, including Stargardt’s disease. The project aims to improve understanding of inherited retinal disease and find patients who are eligible for clinical trials.
- Associate Professor Penny Allen is leading the Bionic Eye Project at CERA. She is testing a bionic eye in people with inherited retinal disease.
How can I help?
You can support CERA’s research into Stargardt’s disease by:
- making a donation
- volunteering for research or being informed about any upcoming clinical trials
- referring yourself or a patient to the national IRD database.