TABLE 1 

Strain-specific H. pylori features that correlate with gastric cancer risk

Gene or regionEncoded protein(s)Feature of gene in H. pylori strainsa
Higher gastric cancer riskLower gastric cancer risk
cag PAICagA and T4SSPresentAbsent
cagAEffector proteinMore EPIYA motifs*Fewer EPIYA motifs
EPIYA-D motif*Lack of EPIYA-D motif
EPIYA-B motif*EPIYT-B motif
High levels of CagA production*Lower levels of CagA production
vacASecreted toxins1, i1, m1 formss2, i2, m2 forms
babAOMPPresentAbsent
sabAOMPIn frameOut of frame
homBOMPPresentAbsent
oipA (hopH)OMPIn frameOut of frame
hopQOMPType I formAbsence of type I form
dupAVirB4 homologAbsentPresent
  • a cagA-positive strains are associated with a higher risk of gastric cancer than are cagA-negative strains. Among cagA-positive strains, those producing CagA with the features indicated with an asterisk are associated with a higher risk of gastric cancer.