Geographic differences in gastric cancer incidence can be explained by differences between Helicobacter pylori strains.
Certain populations with high incidences of Helicobacter pylori infection, such as those in East Asian countries, have high incidences of gastric cancer, while other highly infected populations, such as those in Africa and South Asia, do not. The various rates of gastric cancer associated with different geographic areas can be explained, at least in part, by the differences in the genotypes of H. pylori cagA and vacA. Populations expressing a high incidence of gastric cancer are mostly identical with regions where East Asian type CagA is predominant. In contrast, incidence of gastric cancer is low in Africa, South Asia, and Europe, where strains typically possess Western type CagA. Within East Asia, strains from northern parts, where the incidence of gastric cancer is high, predominantly possess the vacA m1 genotype, whereas the m2 genotype is predominant in southern parts where the gastric cancer incidence is low.
Yamaoka
Yoshio
Y
Department of Medicine-Gastroenterology, Michael E. DeBakey Veterans Affairs Medical Center and Baylor College of Medicine, Texas, USA. yyamaoka@bcm.tmc.edu
Kato
Mototsugu
M
Asaka
Masahiro
M
D000942:Antigens, Bacterial / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D005838:Genotype; D014943:Global Health; D016481:Helicobacter Infections / Q000453:epidemiology* / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics* / Q000472:pathogenicity; D006801:Humans; D015994:Incidence; D013274:Stomach Neoplasms / Q000453:epidemiology* / Q000382:microbiology*; D014774:Virulence
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C074689:VacA protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori