What role does LCT play in allergy?

LCT encodes lactase, the enzyme that breaks down lactose. Lactose intolerance is a digestive condition due to lactase deficiency, not an allergy. Allergies involve IgE-mediated immune responses to proteins, not sugars. There is no strong evidence that LCT variants directly cause or modulate allergic reactions. Some observational studies explore links between lactase persistence (and thus dairy consumption) and allergy risk, but results are inconsistent and confounded. Major allergy guidelines (EAACI, AAAAI) do not mention LCT testing. Direct-to-consumer DNA tests that claim LCT influences allergy are misleading. If you suspect a food allergy, consult an allergist for proper IgE testing. LCT's role is limited to lactose digestion; it does not mediate immune hypersensitivity. Evidence: unclear – no direct human studies linking LCT to allergy outcomes.