Marker

rs601338

rs601338 is a G>A nonsense variant in FUT2 that introduces a premature stop codon at amino-acid position 154 (p.Trp154Ter, historically called W143X), inactivating the fucosyltransferase 2 enzyme. Individuals homozygous for the A allele are 'non-secretors,' unable to add ABO/Lewis blood-group antigens to mucosal secretions, which shifts gut mucosa-associated microbiota composition and alters susceptibility to specific enteric pathogens (e.g., resistance to norovirus, increased susceptibility to some bacterial infections). It is used together with LCT rs4988235 to characterize secretor status and its gut-microbiome associations.

Traits rs601338 reads

Gut secretor status

Gene

FUT2

Reference databases

dbSNP: rs601338

How Biome reads this

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This page is for educational purposes only and is not medical advice. It is not intended to diagnose, treat, cure, or prevent any disease. Genetic results describe tendencies and predispositions, not diagnoses. Always consult a licensed clinician before making decisions about your health, medications, or supplements.