Further species level analysis revealed that several Bifidobacterium species like B. adolescentis (p = 0.005 with respect to NUD/GAS-Hp−; p = 0.003 with respect to NUD/GAS-Hp+; p = 0.009 with respect to GERD-Hp−), B. longum (p = 0.002 with respect to NUD/GAS-Hp−; p = 0.008 with respect to NUD/GAS-Hp+; p = 0.02 with respect to GERD-Hp−), and B. bifidum (p = 0.01 with respect to NUD/GAS-Hp−; p = 0.01 with respect to GERD-Hp−) were present at significantly lower relative abundance specifically for the CA/GU-Hp+ group compared with the other groups (Figure 6D). The gene discussed is HP; the disease is gastroesophageal reflux disease.