Epidemiological link between gastric disease and polymorphisms in VacA and CagA.
Gastritis, peptic ulcer disease, and gastric cancer are a few of the diverse disease manifestations that have been shown to be associated with infection by Helicobacter pylori. Why some individuals develop more severe forms of disease remains largely unknown. In this study, 225 South Korean strains were genotyped for vacA and then analyzed to determine if particular genotypes varied across disease state, sex, or cagA allele. Of these strains, 206 strains carried an s1/i1/m1 allele, 11 strains carried an s1/i1/m2 allele, and 8 strains carried an s1/i2/m2 allele. By using Fisher's exact test, a statistical association between variations in the cagA and vacA alleles was identified (P = 0.0007), and by using log linear modeling, this variation was shown to affect the severity of disease outcome (P = 0.027). Additionally, we present evidence that variation within the middle region of VacA contributes significantly to the distribution of vacA alleles across gender (P = 0.008) as well as the association with disease outcome (P = 0.011). In this South Korean population, the majority of H. pylori strains carry the vacA s1/i1/m1 allele and the CagA EPIYA-ABD allele. These facts may contribute to the high incidence of gastric maladies, including gastric cancer.
Jang
Sungil
S
Department of Oral Biology, Oral Science Research Center, BK21 Project, Yonsei University College of Dentistry, Seoul, South Korea.
Jones
Kathleen R
KR
Olsen
Cara H
CH
Joo
Young Min
YM
Yoo
Yun-Jung
YJ
Chung
In-Sik
IS
Cha
Jeong-Heon
JH
Merrell
D Scott
DS
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005260:Female; D005756:Gastritis / Q000453:epidemiology* / Q000382:microbiology; D005787:Gene Frequency; D005838:Genotype; D016481:Helicobacter Infections / Q000150:complications* / Q000382:microbiology; D016480:Helicobacter pylori / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D006801:Humans; D007723:Korea; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010437:Peptic Ulcer / Q000453:epidemiology* / Q000382:microbiology; D017422:Sequence Analysis, DNA; D013274:Stomach Neoplasms / Q000453:epidemiology* / Q000382:microbiology; D037521:Virulence Factors / Q000235:genetics; D055815:Young Adult
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D004269:DNA, Bacterial; C074689:VacA protein, Helicobacter pylori; D037521:Virulence Factors; C080866:cagA protein, Helicobacter pylori