Evolutionary History of Helicobacter pylori Sequences Reflect Past Human Migrations in Southeast Asia

The human population history in Southeast Asia was shaped by numerous migrations and population expansions. Their reconstruction based on archaeological, linguistic or human genetic data is often hampered by the limited number of informative polymorphisms in classical human genetic markers, such as the hypervariable regions of the mitochondrial DNA. Here, we analyse housekeeping gene sequences of the human stomach bacterium Helicobacter pylori from various countries in Southeast Asia and we provide evidence that H. pylori accompanied at least three ancient human migrations into this area: i) a migration from India introducing hpEurope bacteria into Thailand, Cambodia and Malaysia; ii) a migration of the ancestors of Austro-Asiatic speaking people into Vietnam and Cambodia carrying hspEAsia bacteria; and iii) a migration of the ancestors of the Thai people from Southern China into Thailand carrying H. pylori of population hpAsia2. Moreover, the H. pylori sequences reflect iv) the migrations of Chinese to Thailand and Malaysia within the last 200 years spreading hspEasia strains, and v) migrations of Indians to Malaysia within the last 200 years distributing both hpAsia2 and hpEurope bacteria. The distribution of the bacterial populations seems to strongly influence the incidence of gastric cancer as countries with predominantly hspEAsia isolates exhibit a high incidence of gastric cancer while the incidence is low in countries with a high proportion of hpAsia2 or hpEurope strains. In the future, the host range expansion of hpEurope strains among Asian populations, combined with human motility, may have a significant impact on gastric cancer incidence in Asia

A first absolute chronology for Late Neolithic to Early Bronze Age Myanmar: new AMS C-14 dates from Nyaung'gan and Oakaie

Late prehistoric archaeological research in Myanmar is in a phase of rapid expansion. Recent work by the Mission Archéologique Française au Myanmar aims to establish a reliable Neolithic to Iron Age culture-historical sequence, which can then be compared to surrounding regions of Southeast Asia. Excavations at Nyaung'gan and Oakaie in central Myanmar have provided 52 new AMS dates, which allow the creation of Myanmar's first reliable prehistoric radiometric chronology. They have also identified the Neolithic to Bronze Age transition in central Myanmar, which is of critical importance in understanding long-range interactions at the national, regional and inter-regional level. This research provides the first significant step towards placing late prehistoric Myanmar in its global context

Cristalliser l'histoire : la seconde vie des perles préhistoriques en Thaïlande péninsulaire

La Thaïlande péninsulaire compte peu de vestiges archéologiques à l'exception de perles qui cristallisent des passions dévorantes. Collectées, portées, commercialisées, elles font régulièrement la une des journaux. À partir d'une enquête ethnographique réalisée auprès de la mission archéologique franco-thaïe en péninsule thaïe-malaise, cet article éclaire les pratiques de collecte de ces perles par divers acteurs locaux, et envisage les discours et représentations parfois contradictoires auxquels elles donnent lieu

Prehistoric iron production technologies in the Upper Thai-Malay Peninsula : metallography and slag inclusion analyses of iron artefacts from Khao Sam Kaeo and Phu Khao Thong

This article presents a preliminary attempt to characterise Upper Thai-Malay Peninsula prehistoric iron technologies based on assemblages from two recently excavated coastal sites: Khao Sam Kaeo and Phu Khao Thong. These are the earliest known sites involved in the early trans-Asian exchange that connected the eastern Indian Ocean to the South China Sea from the mid-first millennium bc. It is from this period that iron assemblages start appearing at both continental and insular Southeast Asian sites. Three models have been offered confronting an indigenous vs. Chinese or South Asian impetus for the introduction of iron metallurgy in Southeast Asia. These models are discussed in the light of the metallographic and compositional analyses of iron and slag assemblages from these two sites using optical microscopy, scanning electron microscopy with energy dispersive spectrometry, energy dispersive X-ray fluorescence and slag inclusion analysis techniques, together with other production materials from these and other contemporaneous Southeast Asian sites