The Genetics of Malaria Resistance in Ancient Rome (15 min)

Presenters

Hannah Moots, University of Chicago; David Pickel, Georgetown University; Alessandra Sperduti, Museum of Civilizations, Bioarchaeology Service, Rome; Francesca Candilio, Museum of Civilizations, Bioarchaeology Service, Rome; and Ron Pinhas, independent scholar

Abstract

Malaria is known to have afflicted the Romans since at least the second century C.E., and possibly centuries earlier. Recent paleobiomolecular evidence and numerous ancient literary sources confirm the malaria pathogen’s ancient presence and hint at the disease’s devastation. Given this growing body of knowledge, archaeologists and ancient historians increasingly are taking the disease into consideration when studying ancient Rome. Yet much remains unknown about the disease’s changing prevalence over time and its impact on the population. Research on modern populations has made clear that malaria has been a major selective force in human history, shaping human genomes and resulting in high frequencies of malaria resistant alleles in regions where the disease has long been endemic. Information on the frequency of these alleles in the past would complement existing lines of evidence regarding malaria’s historical impact in Italy, a history that spans two millennia, up until the disease’s ultimate elimination there in the 20th century. We examine the frequencies of known malaria resistance alleles using time-series data from Rome and central Italy, which includes 127 individuals and spans the last 12,000 years. We take a closer look at the timing and context of these allele frequency changes, exploring how selection, migration, or both might be driving these allele frequency changes. We also examine the changing disease ecology of ancient Rome and how this may have played a role in the trends observed.