ABH (Lewis antigen system) Secretor or Non-Secretor status?
FUT2 (Fucosyltransferase 2) Gene
SNP rs601338 A/A non-secretor
SNP rs601338 A/G secretor
SNP rs601338 G/G secretor
(Saliva tested: "non-secretor" and rs601338 A/G secretor)
https://opensnp.org/snps/rs601338
https://www.23andme.com/health/Norovirus-Resistance
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0020113