Abstract
Helicobacter pylori has probably infected the human stomach since our origins and subsequently diversified in parallel with their human hosts. The genetic population history of H. pylori can therefore be used as a marker for human migration. We analysed seven housekeeping gene sequences of H. pylori strains isolated from 78 Senegalese and 24 Malagasy patients and compared them with the sequences of strains from other geographical locations. H. pylori from Senegal and Madagascar can be placed in the previously described HpAfrica1 genetic population, subpopulations hspWAfrica and hspSAfrica, respectively. These 2 subpopulations correspond to the distribution of Niger-Congo speakers in West and most of subequatorial Africa (due to Bantu migrations), respectively. H. pylori appears as a single population in Senegal, indicating a long common history between ethnicities as well as frequent local admixtures. The lack of differentiation between these isolates and an increasing genetic differentiation with geographical distance between sampling locations in Africa was evidence for genetic isolation by distance. The Austronesian expansion that started from Taiwan 5000 years ago dispersed one of the 10 subgroups of the Austronesian language family via insular Southeast Asia into the Pacific and Madagascar, and hspMaori is a marker for the entire Austronesian expansion. Strain competition and replacement of hspMaori by hpAfrica1 strains from Bantu migrants are the probable reasons for the presence of hspSAfrica strains in Malagasy of Southeast Asian descent. hpAfrica1 strains appear to be generalist strains that have the necessary genetic diversity to efficiently colonise a wide host spectrum.
Highlights
The association between Helicobacter pylori and man is very old: humans have probably been infected with H. pylori since their origins [1]
Like human mitochondrial DNA, the global phylogeny of H. pylori sequences consists of two super-lineages
The first contains mitochondrial DNA (mtDNA) haplogroup L0, which is found predominantly in hunter-gatherers in southern Africa, the San, who are the natural hosts of the H. pylori super-lineage hpAfrica2
Summary
The association between Helicobacter pylori and man is very old: humans have probably been infected with H. pylori since their origins [1]. Like human mitochondrial DNA (mtDNA), the global phylogeny of H. pylori sequences consists of two super-lineages. The first contains mtDNA haplogroup L0, which is found predominantly in hunter-gatherers in southern Africa, the San, who are the natural hosts of the H. pylori super-lineage hpAfrica. The other super-lineage contains the human mtDNA haplogroups L1–L6, which correspond to other H. pylori populations [1]. Geographical separation plus founder effects have resulted in distinct bacterial populations with specific geographical distributions [1,2,3,4,5,6,7,8,9]: hpEurope (present in Europe, the Middle East and west and South Asia), hpNEAfrica (northeast Africa), hpAfrica
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
