Peanut Allergies Are Influenced By Genes, Study Shows

Researchers believe that genes may play a role in food allergies.

New findings published the journal Nature Communications show that human genome is associated with peanut allergies in U.S. children, supporting strong evidence that genes play a role in the development of food allergies.

"We always suspected it, but this is the first genome-wide association study (GWAS) that identified a genetic link to well-defined peanut allergy," said the study's principal investigator, Xiaobin Wang, MD, ScD, MPH, the Zanvyl Krieger Professor and director of the Center on the Early Life Origins of Disease at the Johns Hopkins Bloomberg School of Public Health, in a news release.

For the study, researchers analyzed the DNA samples from 2,759 participants enrolled in the Chicago Food Allergy Study (1,315 children and 1,444 of their biological parents.) Most of the children had some kind of food and 1 million genetic markers across the human genome were scanned. Researchers looked for clues to which genes might contribute to an increased risk of developing certain food allerigies, including peanut.

They discovered that a genomic region harboring genes such as HLA-DB and HLA-DR and located on chromosome six was linked to peanut allergy. Furthermore, the study suggested that the HLA-DR and -DQ gene region probably posed significant genetic risk for peanut allergy as it accounted for about 20 percent of peanut allergy in the study population.

However, not everyone with these mutations develops peanut allergies. Researchers believe this may be because epigenetic changes also play a role. Only more research will tell for certain.

Unlike genes themselves, DNA methylation levels can change in response to environmental exposures, with changes that are potentially reversible. When identifying potential environmental factors that alter these DNA methylation levels, researchers could potentially open a new avenue for prevention to treat peanut allergies and other allergic reactions in the future.

"Hopefully, one day, we can manage or prevent food allergies in a safe, simple, effective way," Wang says. "We might be able to use pharmaceutical treatment, but if we can figure out whether a lifestyle, nutrition or environmental change could reduce allergies, that would be even better."