Ancient Plasmodium genomes shed light on the history of human malaria.

Malaria-causing protozoa of the genus Plasmodium have exerted one of the strongest selective pressures on the human genome, and resistance alleles provide biomolecular footprints that outline the historical reach of these species1. Nevertheless, debate persists over when and how malaria parasites emerged as human pathogens and spread around the globe1,2. To address these questions, we generated high-coverage ancient mitochondrial and nuclear genome-wide data from P. falciparum, P. vivax and P. malariae from 16 countries spanning around 5,500 years of human history. We identified P. vivax and P. falciparum across geographically disparate regions of Eurasia from as early as the fourth and first millennia BCE, respectively; for P. vivax, this evidence pre-dates textual references by several millennia3. Genomic analysis supports distinct disease histories for P. falciparum and P. vivax in the Americas: similarities between now-eliminated European and peri-contact South American strains indicate that European colonizers were the source of American P. vivax, whereas the trans-Atlantic slave trade probably introduced P. falciparum into the Americas. Our data underscore the role of cross-cultural contacts in the dissemination of malaria, laying the biomolecular foundation for future palaeo-epidemiological research into the impact of Plasmodium parasites on human history. Finally, our unexpected discovery of P. falciparum in the high-altitude Himalayas provides a rare case study in which individual mobility can be inferred from infection status, adding to our knowledge of cross-cultural connectivity in the region nearly three millennia ago.

Fluorescent Immunohistochemistry: An Important Tool to Reveal Proteins From Tissues in Ancient Mummified Remains.

During the restoration of the Saint Antonio Abate Cathedral in Castelsardo, Sardinia, Italy, numerous human remains were found in a crypt. The burial site contained upwards of 120 individuals organized in successive layers from the bottom of the crypt; of these, 18 partially mummified individuals have been identified, including the last 2 individuals buried in the crypt. In the present study, we focused on these 2 individuals by initially adopting a morphologic and anthropological approach. The anthropological analysis of the remains showed that the 2 bodies were partially mummified and that most of the organs were not available; for this reason, the sex was determined by secondary sexual characteristics of the skulls and the long bones. The aim of this research was to describe the general state of the mummified bodies and tissues by morphologic and ultrastructural analysis using light and electron microscopy techniques. To ensure the preservation of specific tissue proteins, immunohistochemical fluorescence analysis was used. Limited information is available regarding the preservation of mummified tissues. Thus, this study demonstrated the presence of muscle and skin tissue markers in a good state of preservation, even though the tissues had undergone a slow mummification process. Our results demonstrate that several types of tissues and cell proteins may survive over a prolonged period and that these materials survive the postmortem processes.