- Hp Africa 2 is found among Southern African natives (Khoisan)
- Hp Africa 1 is found among West Africans and Bantus (with some penetration in the Khoisan stomachs)
- Hp NE Africa is found at the Middle and Upper Nile and Lake Chad
- Hp Europe is found also in West Asia and North Africa and shows clear signs of being a hybrid of NE Africa and Asia2 (so it’s phylogenetic position is a blend of its parents’)
- Hp Asia2 is from South Asia
- Hp East Asia and Hp Sahul (Australasia) need no further explanation
Category Archives: bacteria
|hpEAsia – Fig. 2 – NJ tree C (supopulation hspEAsia) is a subset of B|
Some north-to-south colonization pattern (interspersed with south-to-north bouts) is also apparent in the tree C but it is hard to understand because it is not clear how it relates with hspEAsian in tree B. It may be related to Han Chinese expansion or to Neolithic flows or a combination of the two.
|hpAsia2 – Fig. 3|
|hpEurope – Fig.1|
This macro-clade shows two subpopulations: ‘Europe’ (including in fact West Asians) and ‘Asia’, which seems centered in India. The migration of this clade to SE Asia should be related to the Hindu (and Buddhist) influences of some 2200 years ago (otherwise it cannot be explained its presence in Thailand and Cambodia).
Update (Jul 22):
It is interesting for background and a wider picture to take a look at this older paper, which is freely available as author’s manuscript at PubMed Central:
Most interesting is surely this image (fig. 1):
|click here for original and legend|
While this paper does not yet mention the Asia 2 clade, it does indicate the other relevant clades as well as their African relatives, some of which are closer, while others are more distant (b).
The first split in this human parasite seems to be between Africa 2 (Southern Africa) and the rest, in agreement with what human genetics tells about our early history in Africa.
Then the lineage seems to divide among a branch remaining in Africa (Africa 1 and Europe 2, aka AE2, centered in West and East Africa respectively) and another one migrating to Asia (Europe 1, centered in India, and East Asia). It seems that Helicobacter pylori also experienced an Out of Africa migration… in our stomachs.
Beurec 2011 (the main paper mentioned above) says:
Strains of the hpEurope population were shown to be hybrids of two ancestral populations, AE1 from central Asia and AE2 from northeast Africa while modern hpEastAsia strains are almost pure descendants of ancestral EastAsia.
This explanation (hat tip to Gioello) was what lead me to find this other paper by Linz et al.