Can FUT2 help with Allergie?

FUT2 (rs601338) determines secretor status: non-secretors have reduced fucosylated glycans in the gut, impairing Bifidobacterium colonization. This can alter immune development and has been linked to increased allergy risk (e.g., hay fever, asthma). Evidence comes from GWAS and observational studies, but effect sizes are modest. FUT2 is one of many factors; diet, microbiome, and environment play larger roles. A DNA test alone cannot diagnose or predict allergies.