Gut Liver.  2012 Jan;6(1):21-28.

Evolutionary History of the Helicobacter pylori Genome: Implications for Gastric Carcinogenesis

• Correa P
• Piazuelo M

Abstract

The genome of the bacterium Helicobacter pylori has evolved over the millennia since its migration out of Africa along with its human host approximately 60,000 years ago. Human migrations, after thousands of years of permanent settlement in those lands, resulted in seven prototypes of genetic populations of H. pylori with distinct geographical distributions. In all continents, present day isolates of H. pylori have molecular markers that reflect population migrations. The colonization of the Americas as well as the slave trade introduced European and African strains to the New World. The relationship between H. pylori genome and gastric cancer rates is linked to the presence of the cagA gene, but the knowledge on this subject is incomplete because other genes may be involved in certain populations. A new situation for Homo sapiens is the absence of H. pylori colonization in certain, mostly affluent, populations, apparently brought about by improved home sanitation and widespread use of antibiotics during the last decades. The disappearance of H. pylori from the human microbiota may be linked to emerging epidemics of esophageal adenocarcinoma, some allergic diseases such as asthma and some autoimmune disorders.

Keyword

Helicobacter pylori; Genome; Gastric carcinogenesis

MeSH Terms

Adenocarcinoma
Africa
Americas
Anti-Bacterial Agents
Asthma
Colon
Genome
Helicobacter
Helicobacter pylori
Human Migration
Humans
Metagenome
Sanitation
Social Problems
Stomach Neoplasms
Anti-Bacterial Agents