Dr. Katia Taba, Board-Certified Ophthalmologist and Retinal Specialist
When there is damage to the retina due to specific issues, degeneration can occur, and it is a serious disorder that should never be overlooked. In adults over the age of 50, age-related macular degeneration (AMD) is the leading cause of blindness. It is estimated that more than 10 million Americans have some degree of AMD.
Dr. Taba of Personalized Retina Care of Naples wants to alert individuals about the signs and seriousness of this disorder. Recently the AAO (American Academy of Ophthalmology) published an article detailing the condition.
Age-related macular degeneration (AMD) is the leading cause of irreversible vision loss in the United States in elderly adults. It is estimated that nearly two million Americans have the advanced form of AMD. This number is projected to more than double over the next two decades.
Risk factors include being over 50 years of age and smoking. Anyone can develop AMD, but lifestyle and diet are major factors in an individual’s risk. And It is clear that genetic factors have a lot of influence on when AMD might start and how it progresses.
Many Genes Influence AMD Risk, But Two Stand Out
Large genome-wide association studies have identified over 30 genes associated with the risk of developing AMD. These kinds of studies look for genes that are more common in people with certain conditions. If a lot of people have a particular variation of a gene and also have a particular condition—while other people without the variation don’t have the condition—that gene is said to be associated with the condition. Variants in all 30-plus of these genes contribute different levels of risk of developing AMD.
Variations in two genes have been more closely connected to both developing AMD and whether it progresses to the advanced stages of the disease. These are:
• The complement cascade (group of genes) on chromosome 1; and
• The ARMS2/HTRA genes on chromosome 10.
The presence of these genetic variants doesn’t mean that someone will definitely develop AMD. These variants mean that one may have a higher risk of AMD or developing advanced disease in the future.
The complement cascade is an essential part of the body’s immune system. It controls a series of proteins that protect against invading pathogens like bacteria and viruses. Complement can sometimes incorrectly target the body’s healthy cells, including cells in the retina.
Some researchers believe that inflammation and immune mechanisms are part of what causes AMD. The connection between complement gene variants and AMD supports this theory. There are several variants of the complement genes, and they create different levels of AMD risk.
While scientists are intensively researching ARMS2/HTRA1, the role of these genes in AMD is not yet understood. It appears there is a strong connection, but we don’t yet know what these genes do.
Other genes associated with increased AMD risk are involved in cholesterol and lipid (fat) metabolism, collagen production, DNA repair, protein binding, and cell signaling. Research on these genes and their role in disease onset and progression is still underway.
In addition, certain gene variants can have a protective effect against AMD, reducing an individual’s risk of developing the disease. These include variants in other parts of the complement and immune gene groups, and other genes that affect lipids.
Genetic Testing and The Future of AMD
Genetic testing is available for some of the AMD risk genes. However, the American Academy of Ophthalmology does not currently recommend genetic testing for AMD. Gene therapy is not available for prevention or management of the disease, so there is no benefit of identifying which genes are involved in any individual’s case of macular degeneration.
As future studies shed more light on AMD and individual genotypes—and if treatment tailored to individuals become available—genetic testing for AMD may become helpful. We may one day have targeted therapies for AMD based on the individual’s genes and lifestyle.
In the meantime, anyone with a family history of AMD should have their eyes examined as recommended by an ophthalmologist, get enough exercise, eat a well-balanced diet and quit smoking. If you have AMD, existing treatments, including vitamin supplements and medications, can be very effective.
Personalized Retina Care of Naples
If you are experiencing any changes in your eye health, whether it is blurry vision, pain, impaired vision, or any other visual irregularities, it is imperative that you see an ophthalmologist right away. The earlier disease or disorders are detected, the better the outcome and treatment options are for you. You will find a friendly and warm environment at Personalized Retina Care of Naples. Please call (239) 325-3970 today to schedule your eye exam. Same-day appointments are still available.
Personalized Retina Care of Naples provides comprehensive diagnosis and treatment for retinal disorders. Dr. Taba also gives second opinions on retinal and general eye conditions. Dr. Taba is a Board-Certified Ophthalmologist and is Fellowship trained in surgical and medical retinal diseases.
There are ways to regain your independence and correct low vision. To find out more, or to schedule your appointment, please call Personalized Retina Care of Naples at (239) 325-3970 today. Same day appointments are often available.
www.retinanaples.com | 239-325-3970
3467 Pine Ridge Rd., Suite 103, Naples 34109
Reference:
1. R. Mukamal, Genetics and Age-Related Macular Degeneration,
AAO, American Academy of Ophthalmologists, April 9, 2009,
https://www.aao.org/eye-health/diseases/age-related-macular-
degeneration-amd-genetics