[Comparative genome analysis of Helicobacter pylori strains]

DNA macroarrays were used to characterize 17 Helicobacter pylori strains isolated in four geographic regions of Russia (Moscow, St. Petersburg, Kazan, and Novosibirsk). Of all genes, 1272 (81%) proved to occur in all strains and to constitute a functional core of the genome, and 293 (18.7%) were strain-specific and greatly varied among the H. pylori strains. Most (71%) of the latter had unknown functions; the remainder included restriction-modification genes (3-9%), transposition genes (2-4%), and genes coding for outer membrane proteins (2-4%). The Russian H. pylori strains did not differ in genome organization or in the number and distribution of strain-specific genes from strains isolated in other countries.