Is FUT2 useful for allergy?

The provided context contains no information about FUT2 or its relevance to allergies. FUT2 (fucosyltransferase 2) is a gene that determines secretor status and has been linked in some studies to gut microbiome composition and, indirectly, to allergy risk. However, the evidence is mostly mechanistic or observational, not from robust clinical trials. Direct, reproducible associations between FUT2 variants and specific allergies are not well established. Without supporting data in the given context, the evidence grade is unclear/marketing. Consumers should not rely on single genes like FUT2 to assess allergy risk. A comprehensive clinical allergy evaluation (e.g., IgE testing, skin prick test) remains the standard of care.