The importance of the HBGA ligands of P[8]-bearing strains in vivo is, nonetheless, well documented since so-called nonsecretor children, who present inactivating mutations in the FUT2 gene, seldom develop symptomatic gastroenteritis caused by P[8]-bearing strains and seroconvert less efficiently than secretor children after vaccination (18, 19, 58, –, 60). Here, FUT2 is linked to gastroenteritis.