Myths vs facts: HLA-DQ2 and allergy

HLA-DQ2 is a genetic marker strongly associated with celiac disease, an autoimmune condition triggered by gluten. It is not an allergy marker. Allergies are IgE-mediated hypersensitivity reactions, whereas celiac disease is a T-cell-mediated autoimmune response. The myth that HLA-DQ2 causes allergies often arises from confusion between intolerances and allergies. In fact, individuals with HLA-DQ2 do not have an increased risk for classic allergies such as pollen, food, or insect venom allergies. The evidence for the celiac association is strong (human-strong), but for allergies there is no reliable evidence. A DNA test for HLA-DQ2 cannot be used to predict allergy risk. Importantly, even for celiac disease, HLA-DQ2 is necessary but not sufficient – most carriers never develop celiac disease. Interpretation of such genetic tests should always be in a clinical context. Consumers should not rely solely on gene variants but seek medical diagnostics.