Elevated rates of horizontal gene transfer in the industrialized human microbiome

Industrialization has impacted the human gut ecosystem, resulting in altered microbiome composition and diversity. Whether bacterial genomes may also adapt to the industrialization of their host populations remains largely unexplored. Here, we investigate the extent to which the rates and targets of horizontal gene transfer (HGT) vary across thousands of bacterial strains from 15 human populations spanning a range of industrialization. We show that HGTs have accumulated in the microbiome over recent host generations and that HGT occurs at high frequency within individuals. Comparison across human populations reveals that industrialized lifestyles are associated with higher HGT rates and that the functions of HGTs are related to the level of host industrialization. Our results suggest that gut bacteria continuously acquire new functionality based on host lifestyle and that high rates of HGT may be a recent development in human history linked to industrialization.Peer reviewe

Addressing the Humanitarian and Environmental Consequences of Atmospheric Nuclear Weapon Tests: A Case Study of UK and US Test Programs at Kiritimati (Christmas) and Malden Islands, Republic of Kiribati

Between 1957 and 1962, the UK and USA conducted 33 atmospheric nuclear weapons test detonations at or close to Malden and Kiritimati (Christmas) Islands (total yield 31 megatons), formerly British colonial territories in the central Pacific region, now part of the Republic of Kiribati. Some 40,000 British, Fijian, New Zealand and US civilian and military personnel participated in the test program and 500 i-Kiribati civilians lived on Kiritimati at the time. This article reviews humanitarian and environmental consequences of the UK and US nuclear weapons testing programs in Kiribati, as well as the policy measures that have addressed them. The authors contend that policy interventions to date have not adequately addressed the needs and rights of test survivors, nor ongoing environmental concerns. They argue that the victim assistance and environmental remediation obligations in the 2017 Treaty on the Prohibition of Nuclear Weapons offer an important new opportunity for addressing the consequences of nuclear detonations in Kiribati, by focusing policy attention and constituting a new field of development assistance