title: Comparative genomics of Helicobacter pylori isolates recovered from ulcer disease patients in England.
abstract: BACKGROUND
  Genomic diversity of H. pylori from many different human populations is largely unknown. We compared genomes of 65 H. pylori strains from Nottingham, England. Molecular analysis was carried out to identify rearrangements within and outside the cag-pathogenicity-island (cag PAI) and DNA sequence divergence in candidate genes. Phylogenetic analysis was carried out based on various high-resolution genotyping techniques.
  
  
  RESULTS
  Analyses of virulence genes (cagT, cagE, cagA, vacA, iceA, oipA and babB) revealed that H. pylori strains from England are genetically distinct from strains obtained from other countries. The toxigenic vacA s1m1 genotype was found to be less common and the plasticity region cluster was found to be disrupted in all the isolates. English isolates showed a predominance of iceA1 alleles and a functional proinflammatory oipA gene. The English H. pylori gene pool revealed several Asian/oriental features. This included the predominance of cagA - glr (cagA right junction) motif types III and II (up to 42%), presence of vacA m1c alleles and phylogenetic affinity towards East Asian / Amerindian gene pools based on fluorescent amplified fragment length polymorphism (FAFLP) analysis and glmM sequence analysis.
  
  
  CONCLUSIONS
  Overall, our results demonstrated genetic affinities of H. pylori in England with both European and the Asian gene pools and some distinctive genetic features of virulence genes that may have evolved in this important European population.
authors.affiliation: Pathogen Evolution Group, Laboratory of Molecular and Cell Biology, Centre for DNA Fingerprinting and Diagnostics (CDFD), Hyderabad, India. farhana@cdfd.org.in
authors.forename: Farhana
authors.initials: F
authors.lastname: Kauser
authors.forename: M Abid
authors.initials: MA
authors.lastname: Hussain
authors.forename: Irshad
authors.initials: I
authors.lastname: Ahmed
authors.forename: Sriramula
authors.initials: S
authors.lastname: Srinivas
authors.forename: S Manjulata
authors.initials: SM
authors.lastname: Devi
authors.forename: Ahmed A
authors.initials: AA
authors.lastname: Majeed
authors.forename: K Rajender
authors.initials: KR
authors.lastname: Rao
authors.forename: Aleem A
authors.initials: AA
authors.lastname: Khan
authors.forename: Leonardo A
authors.initials: LA
authors.lastname: Sechi
authors.forename: Niyaz
authors.initials: N
authors.lastname: Ahmed
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D004739:England / Q000453:epidemiology; D014644:Genetic Variation; D016680:Genome, Bacterial; D023281:Genomics; D016481:Helicobacter Infections / Q000453:epidemiology / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics* / Q000302:isolation & purification*; D006801:Humans; D010802:Phylogeny; D013276:Stomach Ulcer / Q000453:epidemiology / Q000382:microbiology*; D037521:Virulence Factors
chemical_list: D001426:Bacterial Proteins; D037521:Virulence Factors