Researchers are building their understanding of the genetic components of atopic dermatitis. This work may have implications for the treatment, screening, and prevention of the condition.

Atopic dermatitis is one of the most common skin conditions around the globe, affecting an estimated 1 in 5 children. Its hallmark symptoms include dry skin and intense itchiness. Atopic dermatitis can affect many aspects of a person’s well-being, including their sleep and mental health.

Most cases of atopic dermatitis develop within the first 5 years of life. Although many children outgrow the disease as they get older, the symptoms can persist or flare up throughout adolescence and into adulthood.

A family history of atopic dermatitis or other allergy-related conditions, such as asthma or food allergies, is one of the strongest known risk factors for atopic dermatitis. This means that if one person in the family has atopic dermatitis, other family members are likely to, as well.

Although atopic dermatitis is a complex condition resulting from multiple factors, there is a strong genetic component to the disease. Researchers have identified several genetic mutations that are associated with the development of atopic dermatitis.

The genes associated with the development of atopic dermatitis fall broadly into two categories: genes related to the integrity of the skin barrier and immune-related genes.

The skin acts as a barrier that prevents microbes and allergens from getting inside the body. Any disruption to that barrier allows these irritants to get deeper into the skin and cause inflammation, which leads to discoloration and itchiness.

A disrupted skin barrier also allows water to escape more easily, which is why people with atopic dermatitis often experience dry skin and why moisturizers can provide symptom relief.

Research has linked skin barrier disruption to multiple genes, including FLG and KIF3A. Mutations in either of these genes disrupt connections between skin cells, leading to a functional breakdown of the protective barrier of the skin.

On the other hand, mutations in immune-related genes may also increase the likelihood of atopic dermatitis. This suggests that atopic dermatitis is not purely an “outside-in” disease — one in which allergens have easier access through the skin and cause inflammation — and that there is also an “inside-out” component.

That is, dysregulation of the immune system causes widespread inflammation throughout the body that damages the integrity of the skin barrier and causes or worsens the symptoms of atopic dermatitis.

This model helps explain why people with atopic dermatitis have an increased risk of developing other diseases resulting from inflammation, including:

  • atopic diseases, such as asthma, food allergies, and allergic rhinitis
  • autoimmune diseases, such as alopecia, lupus, and inflammatory bowel disease
  • other diseases, such as heart disease, diabetes, and infections

Mutations in a wide variety of immune-related genes may play a role in atopic dermatitis, particularly those encoding proteins involved in fighting off infections.

As the genetics of atopic dermatitis have become clearer, researchers have developed a wide variety of new agents that specifically target the immune factors involved in atopic dermatitis.

These agents target specific processes involved in the development of the disease, so they may offer better control of symptoms. They may also cause fewer side effects than current systemic therapies, which broadly suppress the immune system.

Many of these agents are still under investigation, but the Food and Drug Administration (FDA) has already approved several treatments based on an improved understanding of atopic dermatitis genetics and biology. These treatments are:

  • dupilumab (Dupixent)
  • tralokinumab (Adbry)
  • upadacitinib (Rinvoq)
  • abrocitinib (Cibinqo)

Genetic testing is not currently a factor in decisions around treatment for atopic dermatitis, but this may change as more targeted treatment options get approval, and dermatologists aim for more personalized therapy.

Doctors do not routinely carry out genetic testing for children or adults with skin conditions. However, a better understanding of the genetics of atopic dermatitis and the possible implications for treatment may change this in the future.

The diversity of mutations involved in atopic dermatitis does complicate personalized treatment approaches. Mutations in FLG are among the strongest predictors of atopic dermatitis, but scientists have identified at least 16 different mutations in this gene alone.

It is likely that no single mutation causes the disease and that multiple mutations make a person increasingly susceptible to inflammation and breakdown of the skin barrier.

However, given the association between atopic dermatitis and other diseases, researchers have proposed screening infants for mutations associated with atopic dermatitis. Doing so may help parents or caregivers and healthcare teams take measures to prevent atopic dermatitis and its associated conditions.

Some commercial at-home genetic testing kits check for allergies and allergic diseases such as atopic dermatitis, but it is important to remember that the FDA has not validated all of these tests. People who opt to use at-home genetic tests may benefit from discussing the results and implications with a healthcare professional.

Studies on the genetics of atopic dermatitis have revealed important insights into the mechanisms of disease, which has led to the development of new targeted medications. Even more disease-specific treatment options are on the horizon, and there is interest in using genetic information to guide treatment decision-making in the future.

As research continues, genetic testing may also one day help identify people who have an increased risk of atopic dermatitis. These individuals may benefit from proactive, intensive care to help maintain their skin health.