HP and gastric cancer: The most abundant genus in the non-malignant microbiota of both Chinese and Mexican gastric cancer patients was Helicobacter (Figure 1B), and 99% of the Helicobacter reads [median (interquartile range): 98.8% (98.7–99.3%)] were classified as Hp. As shown in Table 1, the majority of GC patients' stomachs (94% Chinese and 55% Mexican) were colonized by Hp, and 53% Chinese and 28% Mexican gastric microbiota were dominated by Hp (Hp relative abundance >50%).