After Helicobacter pylori, genetic susceptibility to gastric carcinoma revisited.

Genetically, it is possible to distinguish two main forms of gastric carcinoma (GC): a hereditary form in which the initiating genetic alteration is inherited and the remaining mutations are acquired somatically; and a sporadic form in which every mutation is of somatic origin and where the environment is thought to play a major role. Although rare, the identification of germline mutations is proving invaluable in the clinical management of GC families. In the setting of sporadic-type GC it has been shown that individuals infected with Helicobacter pylori have an increased risk of developing GC. Recently, abundant evidence has been collected showing that the risk for sporadic GC development also depends on host genetic factors. Despite providing important insights into the understanding of the disease pathogenesis, the genetic markers we have at present are not sensitive/specific enough to form the basis of a screening strategy.