Distinct diversity of the cag pathogenicity island among Helicobacter pylori strains in Japan.
The severity of Helicobacter pylori-related disease is correlated with the presence of a cag pathogenicity island (PAI). Genetic diversity within the cag PAI may have a modifying effect on the pathogenic potential of the infecting strain. We analyzed the complete cag PAI sequences of 11 representative Japanese strains according to their vacA genotypes and clinical effects and examined the relationship between the diversity of the cag PAI and clinical features. The cag PAI genes were divided into two major groups, a Western and a Japanese group, by phylogenetic analysis based on the entire cag PAI sequences. The predominant Japanese strains formed a Japanese cluster which was different from the cluster formed by Western strains. The diversity of the cag PAI was associated with the vacA and cagA genotypes. All strains with the s1c vacA genotype were in the Japanese cluster. In addition, all strains with the East Asian-type cagA genotype were also in the Japanese cluster. Patients infected with the Japanese-cluster strain had high-grade gastric mucosal atrophy. These results suggest that a distinct diversity of the cag PAI of H. pylori is present among Japanese strains and that this diversity may be involved in the development of atrophic gastritis and may increase the risk for gastric cancer.
Azuma
Takeshi
T
Second Department of Internal Medicine, Faculty of Medical Science, University of Fukui Matsuoka-cho, Yoshida-gun, Fukui 910-1193, Japan. azuma@fmsrsa.fukui-med.ac.jp
Yamakawa
Akiyo
A
Yamazaki
Shiho
S
Ohtani
Masahiro
M
Ito
Yoshiyuki
Y
Muramatsu
Atsushi
A
Suto
Hiroyuki
H
Yamazaki
Yukinao
Y
Keida
Yoshihide
Y
Higashi
Hideaki
H
Hatakeyama
Masanori
M
D000942:Antigens, Bacterial / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism; D016480:Helicobacter pylori / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D010766:Phosphorylation; D010802:Phylogeny; D021381:Protein Transport; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D017027:Protein Tyrosine Phosphatases / Q000378:metabolism
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D047908:Intracellular Signaling Peptides and Proteins; C080866:cagA protein, Helicobacter pylori; C516724:PTPN11 protein, human; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D017027:Protein Tyrosine Phosphatases