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1) WHAT IS AMD (AGE-RELATED MACULAR DEGENERATION)?
Age-related macular degeneration (AMD) is a hereditary ophthalmic pathology.

AMD is a disease associated with aging that gradually destroys sharp, central vision (which allows seeing fine detail).

AMD affects the macula, the part of the eye that allows you to see fine detail.

What are the symptoms?

– Presence of drusens (yellow deposits under the retina)
– That begin to enlarge.
– Blurry areas in central vision.
– Distinguishing colours becomes harder.
– Seeing straight lines as wavy ones (on Wet AMD).

 

 

 

 

 

 

 

 

What and where is the macula?

The macula is the small central portion of the retina, temporal to the optic nerve. It is highly sensitive and responsible
for detailed central vision. The fovea is the very center of the macula. The macula allows us to appreciate detail and perform tasks that require central vision such reading.

Some figures

– AMD is a leading cause of vision loss on people 50 years of age and older, affecting approximately 25-30 million people in the Western world.
– 20 % of elderly people (> 65 years old) suffer of AMD.
– AMD is among the most common causes of blindness in Europe and the USA, affecting one in 15 people over the age of 75.
– Medical experts estimate that of the 500 000 new patients that develop wet AMD every year around the world, 40-60 % will develop predominantly classic lesions during the progression of their disease.
– In France, AMD concerns 1 million people. This figure, due to the increase of the life expectancy, should double in the next 20 years.
– Every year AMD causes more than 200 000 Americans to lose their central vision, and many more are already living with vision loss. In fact, macular degeneration alone has turned the demographics of vision loss upside down in the last two decades.

2) CAUSES AND RISK FACTORS
AMD susceptibility is linked to both genetic and environmental factors.

The main risk factor is age. AMD rarely affects those under age 50 and studies show that people over age 60 are at greater risk than other age groups. Although AMD may occur during middle age, studies show that people over age 60 are clearly at greater risk than other age groups.

Other risk factors include:

– Genetics – family history. Genetic factors have been shown to contribute significantly to the development of AMD. Those with immediate family members who have AMD are at a higher risk of developing the disease; for example having first degree relatives with AMD increases the lifetime risk 2-3 fold.
– Smoking. Smoking may increase the risk of AMD. Studies have found that current and former smokers have up to twice the risk of developing AMD as non-smokers.
– Obesity. Research studies suggest a link between obesity and the progression of early and intermediate stage AMD to advanced AMD.
– Race. Whites are much more likely to lose vision from AMD than African Americans.
– Gender. Women appear to have higher risk than men.

However, vision loss should not be an inevitable consequence of aging (see 4) Why early diagnosis?). In some cases, AMD advances so slowly that people notice little change in their vision. In others, the disease progresses faster and may lead to a loss of vision in both eyes.

3) AMD AND GENETICS

The increased risk of AMD related to family history demonstrates that genetics play a significant role in development of the disease. Individuals with a single relative with AMD are twice as likely to develop the disease, while those with two or more relatives are nearly four times as likely to be diagnosed. The risk is even higher if the affected family members were diagnosed before the age of 65. Therefore, early genetic diagnosis helps substantially to start the right treatment to fight against the disease.

Variants in different regions of the genome have been identified that increase the risk of developing AMD:

– a variant in the CFH gene on chromosome 1
– a variant in the HTRA1 gene on chromosome 10

Together CFH and HTRA1 risk variants increase the odds of having AMD by more than 40 times.

4) WHY EARLY DIAGNOSIS?

AMD cannot be reversed. However nowadays, therapies are available that can slow the progression of the disease. Early diagnosis is also an important part of controlling disease progression. All together, early detection, diagnosis and treatment can lead to better visual outcomes. The earlier you understand your risk level, the better your chances are to save your sight.

When you understand the risk, your eye doctor can develop a personalized program to manage the disease. Monitoring and treatment can begin before the symptoms progress, enabling you to slow down or prevent the progression of AMD.

People at risk for AMD, including those over the age of 50 and those with a family history of AMD, should have their eyes examined regularly, learn to recognize the signs of AMD, and take steps to reduce their risk for developing AMD.

5) WHO CAN PRESCRIBE GENETIC TESTING FOR AMD?

Your eye doctor or your physician.

6) WHO CAN DO AMD GENETIC TESTING?

About the analysis

A simple genetic test can determine your risk of losing your vision from AMD.

The sampling: The sampling is painless, non-invasive and avoids blood sample collection (specially appreciated by children, but also adults).

The tests: this test uses a saliva sample on blotting paper to detect the presence of certain genetic markers that are known to be responsible for vision loss. These genetic markers can then be analyzed to determine exactly how high your risk is of losing your sight.

IGNA proposes a study of two variants strongly associated to AMD development: