Expert Reviewed By: Dr. Brandon Colby MD
Stargardt Disease, a recessive genetic disorder, is the most common form of inherited juvenile macular degeneration. It affects approximately one in 10,000 people and is characterized by progressive vision loss, typically starting in childhood or adolescence. This article aims to provide an understanding of Stargardt Disease, its diagnosis, and the role of genetic testing in managing this disorder.
Understanding Stargardt Disease
Stargardt Disease is caused by mutations in the ABCA4 gene, which is responsible for producing a protein that helps to remove potentially harmful byproducts of the visual cycle in the retina. These byproducts can accumulate and damage the light-sensitive cells in the macula, leading to progressive vision loss. The disease is inherited in an autosomal recessive pattern, meaning that an individual must inherit two mutated copies of the ABCA4 gene (one from each parent) to develop the condition.
Common symptoms of Stargardt Disease include difficulty reading, blurry or distorted central vision, and sensitivity to bright light. Over time, the disease can progress to affect peripheral vision and night vision as well.
Diagnosing Stargardt Disease
Diagnosis of Stargardt Disease typically begins with a comprehensive eye exam, including a visual acuity test and a dilated fundus examination. The eye doctor may also use imaging techniques such as optical coherence tomography (OCT) and fundus autofluorescence (FAF) to assess the health of the retina and detect any abnormalities.
Another diagnostic tool is the electroretinogram (ERG), which measures the electrical responses of the retina to light stimulation. This test can help differentiate Stargardt Disease from other retinal disorders and provide information about the severity of the condition.
The Role of Genetic Testing in Stargardt Disease
Confirming the Diagnosis
Genetic testing is a critical component of diagnosing Stargardt Disease, as it can confirm the presence of two mutated copies of the ABCA4 gene. This information can help to differentiate the condition from other retinal disorders with similar symptoms, such as age-related macular degeneration or cone-rod dystrophy.
Carrier Testing and Family Planning
Genetic testing can also be useful for individuals who have a family history of Stargardt Disease and are considering having children. By identifying whether a person is a carrier of a mutated ABCA4 gene, couples can make informed decisions about family planning and assess the risk of passing the condition on to their offspring.
Participation in Clinical Trials and Future Therapies
Researchers are currently working on developing new treatments for Stargardt Disease, including gene therapy and stem cell therapy. Genetic testing can help identify individuals who may be eligible to participate in clinical trials for these experimental therapies. Additionally, as new treatments become available, having a confirmed genetic diagnosis may be necessary to access these therapies.
Conclusion
Stargardt Disease is a challenging condition that can significantly impact an individual's quality of life. Understanding the genetic basis of the disease, obtaining an accurate diagnosis, and exploring the potential benefits of genetic testing are critical steps in managing this disorder. As research continues to advance, genetic testing may play an increasingly important role in the development and implementation of new therapies for Stargardt Disease.
About The Expert Reviewer
Dr. Brandon Colby MD is a US physician specializing in the personalized prevention of disease through the use of genomic technologies. He’s an expert in genetic testing, genetic analysis, and precision medicine. Dr. Colby is also the Founder of and the author of Outsmart Your Genes.
Dr. Colby holds an MD from the Mount Sinai School of Medicine, an MBA from Stanford University’s Graduate School of Business, and a degree in Genetics with Honors from the University of Michigan. He is an Affiliate Specialist of the American College of Medical Genetics and Genomics (ACMG), an Associate of the American College of Preventive Medicine (ACPM), and a member of the National Society of Genetic Counselors (NSGC)