Almost 2 percent of Canadian children develop peanut allergies, which can trigger fatal anaphylactic reactions. By studying the genomes of people with and without peanut allergies, researchers identified several genes that make people more likely to suffer from peanut allergies.
Armed with this information, researchers hope to identify children who are most likely to develop allergies so that action can be taken to minimize their risk.
One of the genes identified, c11orf30/EMSY (EMSY), was shown to be an important player in both peanut and food allergies. Previously linked to several other allergy-related conditions, including eczema, asthma and hay fever, this is the first time EMSY was shown to increase risk of food allergies.
EMSY is involved in the epigenetic regulation of other genes: it acts like a dimmer switch that can turn genes up or down, which can trigger or diminish genetic medical conditions. The exact gene that EMSY acts on to cause allergies is still unknown.
This study adds to the growing evidence that specific allergies are not inherited, but that a genetic tendency for allergies in general can be.
Food allergies develop as a result of both genetic and environmental factors, which means that controlling exposure to allergens like peanuts could help prevent them. In fact, earlier exposure to peanuts, before a child’s first birthday, was proven to decrease peanut allergy risk in a clinical trial.
The study was an international collaboration that included researchers from Queen’s University, McGill University, the University of British Columbia, and the University of Calgary.
The team analyzed DNA from 850 peanut allergy sufferers from the Canadian Peanut Allergy Registry, alongside 1,000 Canadians without a peanut allergy. They searched over 7.5 million genetic markers across the genome, comparing the two groups for clues on which might increase peanut allergy risk in what is known as a genome-wide association study. The team’s international collaborators also collected and analyzed data from American, Australian, German, and Dutch populations.
Understanding the genetic link to allergies could help researchers uncover targeted therapies, all while doctors apply best practices to help identify patients, reduce their risk, and manage their symptoms.