Disclaimer: This article is for informational purposes only and is not intended to diagnose any conditions. LifeDNA does not provide diagnostic services for any conditions mentioned in this or any other article.

It is estimated that 8 percent of people around the world have signs of age-related macular degeneration. The condition currently affects about 11 million Americans and 170 million people worldwide, and the prevalence is expected to increase over the coming decades as the proportion of older people in the population increases.

Age-related macular degeneration is a chronic eye condition that commonly leads to vision loss in seniors, making it a leading cause of blindness in the aging population. Understanding age-related macular degeneration is important, not only because of its growing impact, but also to help people recognize early warning signs, reduce risk through healthy lifestyle choices, and explore available treatments that can slow its progression and preserve vision for as long as possible.

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What Is Age-Related Macular Degeneration?

Age-related macular degeneration or AMD, is an eye disease that slowly damages a part of the eye called the macula. The macula is located in the center of the retina, the light-sensitive layer at the back of your eye ball, and it’s responsible for your central vision; the sharp, clear vision you need to read, recognize faces, and see fine details as well as colors. 

 

When the macula becomes damaged, your central vision gets blurry or distorted. You might still have side peripheral vision, but the center of what you see may look blurry, wavy, or even dark. Over time, this can make it hard to do everyday things like reading or doing something more detailed. 

What Are The Two Types of Age-Related Macular Degeneration? 

 

  • Dry Age-Related Macular Degeneration: The more common form of age-related macular degeneration, affecting about 80 to 90 percent of people with AMD. It develops gradually as the macula, the part of the retina responsible for sharp central vision thins over time. Small yellow deposits called drusen build up under the retina, which may interfere with normal cell function. Vision loss in dry AMD tends to be slow and progressive, often starting with mild blurriness or difficulty seeing details, especially in low light. While dry AMD usually causes less severe vision loss than the wet form, it may still make everyday tasks like reading and recognizing faces challenging. In some cases, dry AMD can progress to the more serious wet form.

 

  • Wet Age-Related Macular Degeneration: Less common but much more serious than dry AMD. It occurs when abnormal blood vessels grow underneath the retina and macula. These vessels are fragile and prone to leaking blood and fluid, which damages the macula quickly and may cause sudden and severe vision loss. Symptoms often include distorted or wavy vision and dark spots appearing in the center of vision. Because wet AMD may cause rapid deterioration, early diagnosis and treatment are crucial. Treatments such as injections that block the growth of abnormal blood vessels or laser therapy may help slow the progression and prevent further vision loss.

 

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What Are The Symptoms of Age-Related Macular Degeneration?

  • Blurry or distorted central vision: This means that the center part of your vision, where you see the most detail, becomes unclear or warped. For example, straight lines might look bent or wavy, and things you focus on may appear fuzzy or out of focus.
  • Difficulty reading or recognizing faces: As your central vision gets worse, it can become hard to see small letters clearly or to tell who someone is just by looking at their face, even if they are nearby.
  • A dark or empty area in the center of vision: Sometimes a shadow or blank spot appears right in the middle of what you’re looking at. It can look like a gray or black patch that blocks part of your view.
  • Colors appearing less vibrant:  Colors might start to look duller or less bright than they used to be. This happens because the damaged area of your eye affects how well you see colors.

What Causes of Age-Related Macular Degeneration?

The exact cause of age-related macular degeneration (AMD) is not fully understood, but researchers agree that it develops due to a mix of genetic predispositions and environmental influences. This means that while some people may inherit gene variants that increase their risk, lifestyle and health factors also play a significant role in whether the disease develops or worsens.

  • Age is the most significant risk factor for AMD. The condition primarily affects people over the age of 50, and the likelihood of developing it increases as you get older. This is because, over time, the cells in the retina can deteriorate naturally, making older adults more vulnerable to damage.
  • Genetics also contribute to AMD risk. If you have family members who have had the disease, your chances of developing it are higher. Scientists have identified specific gene variations linked to AMD, which can affect how the retina ages and responds to damage.
  • Ethnicity influences AMD prevalence as well. Studies show that people of European descent are more likely to develop AMD compared to African Americans, for example. The reasons for this difference are still being researched but may involve genetic and environmental factors.
  • Smoking is one of the most significant modifiable risk factors. Smoking doubles the risk of AMD and accelerates its progression by damaging blood vessels and increasing oxidative stress in the retina.

Genetics on Age-Related Macular Degeneration 

GWAS have helped scientists discover that genetics plays a major role in age-related macular degeneration. These studies look at the genes of thousands of people to find patterns. So far,  research studies  have found over 30 genes that may be involved in increasing a person’s risk of developing AMD.

Two genetic areas have shown the strongest link to AMD. One contains a group of immune system genes called the complement cascade, found on chromosome 1. The other involves the ARMS2 and HTRA1 genes on chromosome 10. The complement system normally protects the body by attacking harmful bacteria and viruses. But in some people, it may overreact and mistakenly damage healthy cells in the retina. This can lead to inflammation and vision loss. This is why many scientists believe that inflammation is one of the main causes of AMD.

Researchers aren’t exactly sure how the ARMS2 and HTRA1 genes work, but they do know these genes are closely tied to both the development of AMD and how quickly it gets worse. It’s important to understand that having these genetic changes doesn’t mean you will definitely get AMD. It simply means your risk is higher. On the other hand, some people may have gene variants that actually protect them and lower their risk of getting the disease.

The Population Architecture Using Genomics and Epidemiology (PAGE) study showed that the genetic risk markers for age-related macular degeneration (AMD) vary among different ethnic groups, such as Mexican Americans, Asian Americans, African Americans, and non-Hispanic White Europeans. For example, major risk  variants in genes like ARMS2 and CFH, which are common risk factors in White Europeans, were not significant in non-European populations. Similarly, a research study in East Asians found different genetic variants related to cholesterol and lipid metabolism that affect AMD risk, and these variants interacted with factors like high HDL cholesterol levels.

These findings highlight that genetic risk for AMD can differ greatly between ethnic groups. However, these differences don’t fully explain why some populations have lower rates of AMD. In some groups, protective genetic variants may play a bigger role. For example, in Timor-Leste, AMD is very rare, and although the risk allele of the HTRA1 gene was at a significantly higher frequency in the Timorese, people there often carry protective gene variants of CFH and other genes, rather than all the typical risk variants seen in other populations.

This shows that protective gene variants might be just as important, or even more important, than risk genes in determining who develops AMD. To better understand these differences, future studies need to look at both genetics and environmental factors across diverse populations. This knowledge will be essential for developing personalized medicine approaches that work for each one of us.

Can You Inherit Age-Related Macular Degeneration?

You can’t directly inherit AMD like some other diseases, but it may run in families due to many of the same inherited genetic variants. If a parent or sibling has it, your risk is higher. About 15 to 20 percent of people with age-related macular degeneration have a close relative who also has it. 

Diagnosis of Age-Related Macular Degeneration

Diagnosing age-related macular degeneration typically involves a comprehensive eye exam performed by an optometrist or ophthalmologist. Since AMD often develops slowly and may not cause noticeable symptoms at first, regular eye exams are important especially for adults over the age of 50 or those with a family history of the disease.

Early diagnosis of AMD is important because it allows for timely treatment and lifestyle changes that may slow the disease and protect your vision. If you experience any changes in vision such as blurriness, distortion, or dark spots, schedule an eye exam as soon as possible.

Can you Treat Age-Related Macular Degeneration?

Although there is currently no cure for age-related macular degeneration, there are treatments that can slow its progression, preserve remaining vision, and reduce the impact on daily life, especially if the condition is caught early. Here are some steps to protect your vision:

  • Don’t smoke: Smoking significantly increases your risk of developing age-related macular degeneration and makes it worse if you already have it.
  • Eat a nutrient-rich diet: Leafy greens, fish, and foods high in antioxidants support eye health.
  • Wear sunglasses: Protect your eyes from harmful UV rays by wearing sunglasses outdoors.
  • Exercise regularly: Staying active helps manage blood pressure, cholesterol, and weight, all of which may affect eye health.
  • Get regular eye exams : Regular eye exams are important especially after the age of 50, even if you don’t notice symptoms. Early detection makes a big difference in treatment success.

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