While the specific causes of food allergies are unknown, they undoubtedly involve a complex interplay of genetics and environment. Studies of twins suggest approximately 80 percent of the risk for food allergies is heritable. Only now has research begun to make greater inroads into elucidating the specific genes responsible for the development of food allergy.
In the world’s largest study into the genetic causes of food allergies, researchers from Germany and the United States carried out genome-wide association studies on 497 participants with food allergy diagnosed by oral food challenge, and 2387 controls. Although resource intensive, oral food challenge is considered the gold standard for food allergy diagnosis and was critical to the success of this large scale research program.
The study discovered a total of five genetic risk loci for food allergies. Four of them are associated with all food allergies. The other appears specific to peanut allergy. Four of the five identified risk loci show a strong correlation with known loci for not only atopic dermatitis and asthma, but also for other chronic inflammatory diseases like Crohn’s disease and psoriasis as well as autoimmune disorders.
All identiﬁed loci are involved in immunological regulation or epithelial barrier function, emphasising the role of both mechanisms in food allergy.
This new information may help to provide a basis for the development of better diagnostic tests for food allergies, and support further work to determine the causes of food allergy as well as improved treatment strategies.
Reference: Marenholz et al. 2017 Nature Communications Vol. 8. doi:10.1038/s41467-017-01220-0 Download the Open Access paper here.
Additional reporting: Max Delbrück Center for Molecular Medicine media release.