title: Helicobacter pylori cagA gene variants in Malaysians of different ethnicity.
abstract: We have defined DNA repeat variability in the 3'-terminus of the cagA gene of Helicobacter pylori strains from Malaysian patients of different ethnicities. We identified different alleles based on the EPIYA repeats. cagA types A-B-D and A-B-B-D are more similar to the sequence of Japanese strains, whereas cagA types A-B-C, A-B-C-C, A-B and A-C displayed similarity to strain 26695 sequences. A significant association was found between cagA genotypes and patients' ethnicity, with cagA type A-B-D being predominantly isolated from Chinese patients and cagA type A-B-C from Malays and Indians. Our data further corroborate the possibility that variant biological activity of CagA may affect the host specificity and/or pathogenicity of H. pylori.
authors.affiliation: UKM Medical Molecular Biology Institute (UMBI), Universiti Kebangsaan Malaysia (UKM), Jalan Yaacob Latiff, Bandar Tun Razak, 56000 Cheras, Kuala Lumpur, Malaysia. ramelah@mail.hukm.ukm.my
authors.forename: Ramelah
authors.initials: R
authors.lastname: Mohamed
authors.forename: Alfizah
authors.initials: A
authors.lastname: Hanafiah
authors.forename: Isa M
authors.initials: IM
authors.lastname: Rose
authors.forename: Mohd Rizal A
authors.initials: MR
authors.lastname: Manaf
authors.forename: Shiekh Anwar
authors.initials: SA
authors.lastname: Abdullah
authors.forename: Ismail
authors.initials: I
authors.lastname: Sagap
authors.forename: A
authors.initials: A
authors.lastname: van Belkum
authors.forename: Jasmi A
authors.initials: JA
authors.lastname: Yaacob
mesh_terms: D000595:Amino Acid Sequence; D000942:Antigens, Bacterial / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D016481:Helicobacter Infections / Q000453:epidemiology* / Q000208:ethnology / Q000382:microbiology*; D016480:Helicobacter pylori / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008296:Malaysia / Q000453:epidemiology / Q000208:ethnology; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D044469:Racial Groups; D012091:Repetitive Sequences, Nucleic Acid; D017422:Sequence Analysis, DNA
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D004269:DNA, Bacterial; C080866:cagA protein, Helicobacter pylori