Macular degeneration is not always hereditary, but a family history of the condition is a risk factor. Variations in certain genes may play a role in developing the condition.

People may refer to the condition as age-related macular degeneration (AMD or ARMD), as it usually affects older adults. Family history is a major risk factor for the condition.

In the United States, almost 2 million people have AMD, which is the leading cause of irreversible vision loss. Experts estimate this figure may double in the next 20 years.

AMD is the main cause of vision loss in people ages 50 or above.

This article explains macular degeneration, its causes and risk factors, and whether it is hereditary.

According to the BrightFocus Foundation, genetics may play a part in AMD development in around 3 out of 4 cases.

Certain genes can increase the risk of developing AMD. Two genes — factor H and factor B — play a role in regulating inflammation within the immune system.

In 74% of people with AMD, these genes have certain variants that may link to an increased risk of developing the condition.

Other genes that can play a role in the development of AMD include:

  • the PLEKHA1 gene on chromosome 10
  • a variation of the LOC387715 gene, particularly if a person also smokes
  • a mutation in the HTRA1 gene
  • complement C3 variant

There are over 30 genes that are associated with the risk of developing AMD.

In particular, two genes that may have a close connection with AMD and how it progresses are the complement cascade, part of the immune system, on chromosome 1, and the ARMS2/HTRA genes on chromosome 10.

People with these particular gene variants may have a higher risk of developing AMD.

There are also certain variants of genes that can help protect against AMD and may lower the risk of developing it.

Doctors do not recommend genetic testing for AMD at this time.

Although genetics can play a part, research suggests a combination of factors can contribute to AMD. These include:

Other factors that may contribute to the development of AMD include:

  • Cigarette smoking: People who smoke are up to four times more likely to have AMD than those who have never smoked. Current smokers may develop AMD up to 10 years earlier than people who have never smoked. Smoking causes ADM to progress faster and be less responsive to treatment.
  • Nutrition: A higher intake of saturated and trans fats increases the risk of AMD progressing to the advanced stages of the disease.
  • Obesity: This has a significant association with an increased risk of AMD progression.
  • Cardiovascular risk factors: Higher inflammatory markers relating to cardiovascular risk may also signal AMD risk.

Risk factors for developing AMD also include:

Below are answers to some common questions about macular degeneration.

Does macular degeneration always run in families?

Although a family history of AMD increases the risk of developing the condition, lifestyle and environmental factors also play an important part.

If people have a family history of AMD, taking the following steps may help reduce the risk of developing the condition:

  • avoiding smoking
  • exercising regularly and staying physically active
  • maintaining blood pressure and cholesterol levels within a healthy range
  • eating a healthy, balanced diet that includes dark green leafy vegetables and fish, and limiting saturated fat

Can I get a test for macular degeneration?

People can consult an eye doctor to test for AMD. An eye doctor will carry out a dilated eye exam by giving a person eye drops to dilate the pupil to examine it for any disorders.

Another test is an optical coherence tomography (OCT) test, in which an eye doctor will take images of the inside of the eye using an OCT machine.

If people have a family history of AMD or other risk factors, it is important for them to attend regular eye exams.

What are the early warning signs of macular degeneration?

Early AMD may not cause symptoms. In the intermediate stages of AMD, people may notice mild symptoms, such as blurriness in their central vision and difficulty seeing in low lighting.

In the later stages of dry AMD, or with wet AMD, people may experience:

  • straight lines appearing as crooked or wavy
  • a blurry area or blank spots in the center of their vision
  • colors appearing less bright
  • difficulty seeing in low lighting

People will need to contact a doctor if they have any symptoms of early or late AMD.

Can you stop the progression of macular degeneration?

There is no cure for AMD. However, eating a nutritious diet, exercising regularly, and quitting smoking can help slow the progression. Taking dietary supplements, such as vitamins C and E, lutein, and zinc, can also help. Not everyone with early stage AMD progresses into having late stage AMD, and not everyone with late AMD will develop blindness.

Certain genes can increase the risk of macular degeneration, along with lifestyle and environmental factors, such as smoking, high cholesterol and blood pressure, and eating a diet high in saturated fats.

If people have a family history of macular degeneration, getting regular eye exams, staying physically active, and eating a balanced, healthy diet may all help reduce the risk of developing the condition.