Genetic variability within Helicobacter pylori.

One of the striking characteristics of the human gastric pathogen Helicobacter pylori is extensive genetic diversity between different strains. During the last years, intensive research using genomic, molecular genetic and population genetic approaches has permitted to quantitate the diversity in H. pylori, to define its characteristics, and to understand the mechanisms that generate diversity in this global pathogen. This review summarizes the recent developments in this rapidly moving field and discusses the significance of genomic heterogeneity and nucleotide sequence diversity in the contexts of H. pylori epidemiology and pathogenesis.