Significant association between PTPN11 polymorphism and gastric atrophy among Japanese Brazilians.

Abstract

BACKGROUND:

Helicobacter pylori, especially the cytotoxin-associated antigen A (cagA)-positive strains, plays a crucial role in the development of gastric atrophy and gastric cancer. CagA delivered into gastric epithelial cells combines with src homology 2 domain-containing protein tyrosine phosphatase-2 (SHP-2), possibly leading to atrophy/cancer. Our previous study found that a single-nucleotide polymorphism (SNP; IMS-JST057927) of the PTPN11 gene encoding SHP-2, was associated with gastric atrophy among H. pylori-seropositive subjects. This study aimed to examine the reproducibility of the association among Japanese residing in a different circumstance.

METHODS:

The subjects were 918 healthy adult Japanese Brazilians from four different areas in Brazil. Blood was sampled from March to May 2001. The target SNP in intron 3 of PTPN11 was genotyped by polymerase chain reaction with confronting two-pair primers (PCR-CTPP). Gastric atrophy was evaluated with serum pepsinogens (PGs); PG I, less than 70 ng/dl and PG I/II ratio, less than 3.

RESULTS:

The genotype frequency of PTPN11 was in Hardy-Weinberg equilibrium: 65.5% for G/G, 30.4% for G/A, and 4.1% for A/A. The PTPN11 polymorphism had no significant association with H. pylori seropositivity. Among the H. pylori-seropositive subjects, the odds ratios (ORs) of gastric atrophy were 0.93 (95% confidence interval [CI], 0.59-1.47) for the G/A genotype and 0.31 (95% CI, 0.10-0.95) for the A/A genotype, compared with the G/G genotype.

CONCLUSIONS:

The present study reproduced the significant association between the A/A genotype and reduced risk of gastric atrophy among Japanese outside Japan. According to the Japan Single Nucleotide Polymorphisms (JSNP) database (db)SNP data, the G allele is very frequent among Japanese and rare in Caucasians. This fact may partly explain the distribution of gastric atrophy/cancer in the world.

• Authors: Sayo Kawai, Yasuyuki Goto, Lucy S Ito, Sueli M Oba-Shinjo, Miyuki Uno, Samuel K Shinjo, Suely K N Marie, Yoshiko Ishida, Kazuko Nishio, Mariko Naito, Nobuyuki Hamajima
• Journal: Gastric cancer : official journal of the International Gastric Cancer Association and the Japanese Gastric Cancer Association (Gastric Cancer) Vol. 9 Issue 4 Pg. 277-83 ( 2006) ISSN: 1436-3291 [Print] Japan
• PMID: 17235629 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Intracellular Signaling Peptides and Proteins
• Protein Phosphatase 2
• PTPN11 protein, human
• Protein Tyrosine Phosphatase, Non-Receptor Type 11
• Protein Tyrosine Phosphatases
• SH2 Domain-Containing Protein Tyrosine Phosphatases

Topics

• Adult
• Aged
• Asian People (genetics)
• Brazil
• Female
• Gastritis, Atrophic (genetics, microbiology)
• Genetic Predisposition to Disease
• Genotype
• Helicobacter Infections (complications)
• Helicobacter pylori (pathogenicity)
• Humans
• Intracellular Signaling Peptides and Proteins (genetics)
• Japan
• Male
• Middle Aged
• Polymorphism, Single Nucleotide
• Protein Phosphatase 2
• Protein Tyrosine Phosphatase, Non-Receptor Type 11
• Protein Tyrosine Phosphatases (genetics)
• SH2 Domain-Containing Protein Tyrosine Phosphatases
• src Homology Domains