Ancient DNA analyses of remains of the Medici family (16th century) provide insights into the genetic variation of Plasmodium falciparum.

We evaluated the presence of six Plasmodium species in osteological remains from Grand Duke Francesco I de' Medici (GDFIDM; 1541-1587) and Cardinal Giovanni de' Medici (CGDM; 1543-1562). Targeted enrichment sequencing for mitochondrial genomes recovered 1,865 and 185 base pairs (bp) of P. falciparum from CGDM and GDFIDM, respectively, and 43 bp of P. malariae from GDFIDM. The CGDM P. falciparum sequence represents a previously uncharacterized haplotype with two unique mutations in intergenic and cytochrome c oxidase subunit 1 loci. Network analyses using nine additional ancient samples (Iron Age- 1940s) suggest that this haplotype is closely related to six sequences from Europe, Taiwan, and the Caribbean; the haplotype likely originated from a demographic expansion in Europe. Our study discovered a previously uncharacterized P. falciparum strain from the Italian Renaissance, increasing our knowledge of the diversity of this species and underscoring the use of ancient DNA for the detection and diagnosis of malaria.