Ancient DNA as a tool for medical research

Lessons from ancient pathogens

Ancient infectious diseases and microbes can be used to address contemporary disease.

Ancient Diseases in Vertebrates: Tumours through the Ages

Paleo-oncology studies neoplastic diseases in fossilised animals, including human remains. Recent advancements have enabled more accurate diagnoses of ancient pathologies despite the inherent challenges in identifying tumours in fossils-such as the rarity of well-preserved specimens, the predominance of bone remains, and the difficulty in distinguishing neoplastic from non-neoplastic lesions. This study compiles reports of tumours in fossilised animals, highlighting that neoplasms are present in a wide range of vertebrates and drawing comparisons to modern instances of similar diseases. The findings underscore the multifactorial aetiology of tumours, which involves genetic, environmental, and lifestyle factors, and suggest that tumours have been around for at least 350 million years.

The genetic changes that shaped Neandertals, Denisovans, and modern humans

Modern human ancestors diverged from the ancestors of Neandertals and Denisovans about 600,000 years ago. Until about 40,000 years ago, these three groups existed in parallel, occasionally met, and exchanged genes. A critical question is why modern humans, and not the other two groups, survived, became numerous, and developed complex cultures. Here, we discuss genetic differences among the groups and some of their functional consequences. As more present-day genome sequences become available from diverse groups, we predict that very few, if any, differences will distinguish all modern humans from all Neandertals and Denisovans. We propose that the genetic basis of what constitutes a modern human is best thought of as a combination of genetic features, where perhaps none of them is present in each and every present-day individual.

Uncovering the Holocene roots of contemporary disease-scapes: bringing archaeology into One Health

The accelerating pace of emerging zoonotic diseases in the twenty-first century has motivated cross-disciplinary collaboration on One Health approaches, combining microbiology, veterinary and environmental sciences, and epidemiology for outbreak prevention and mitigation. Such outbreaks are often caused by spillovers attributed to human activities that encroach on wildlife habitats and ecosystems, such as land use change, industrialized food production, urbanization and animal trade. While the origin of anthropogenic effects on animal ecology and biogeography can be traced to the Late Pleistocene, the archaeological record-a long-term archive of human-animal-environmental interactions-has largely been untapped in these One Health approaches, thus limiting our understanding of these dynamics over time. In this review, we examine how humans, as niche constructors, have facilitated new host species and 'disease-scapes' from the Late Pleistocene to the Anthropocene, by viewing zooarchaeological, bioarchaeological and palaeoecological data with a One Health perspective. We also highlight how new biomolecular tools and advances in the '-omics' can be holistically coupled with archaeological and palaeoecological reconstructions in the service of studying zoonotic disease emergence and re-emergence.

Going local with ancient DNA: A review of human histories from regional perspectives

Ancient DNA (aDNA) has added a wealth of information about our species' history, including insights on genetic origins, migrations and gene flow, genetic admixture, and health and disease. Much early work has focused on continental-level questions, leaving many regional questions, especially those relevant to the Global South, comparatively underexplored. A few success stories of aDNA studies from smaller laboratories involve more local aspects of human histories and health in the Americas, Africa, Asia, and Oceania. In this Review, we cover some of these contributions by synthesizing finer-scale questions of importance to the archaeogenetics field, as well as to Indigenous and Descendant communities. We further highlight the potential of aDNA to uncover past histories in regions where colonialism has neglected the oral histories of oppressed peoples.