Whole genome resequencing of the human parasite Schistosoma mansoni reveals population history and effects of selection

AbstractSchistosoma mansoniis a parasitic fluke that infects millions of people in the developing world. This study presents the first application of population genomics toS. mansonibased on high-coverage resequencing data from 10 global isolates and an isolate of the closely-relatedSchistosoma rodhaini, which infects rodents. Using population genetic tests, we document genes under directional and balancing selection inS. mansonithat may facilitate adaptation to the human host. Coalescence modeling reveals the speciation ofS. mansoniandS. rodhainias 107.5–147.6KYA, a period which overlaps with the earliest archaeological evidence for fishing in Africa. Our results indicate thatS. mansonioriginated in East Africa and experienced a decline in effective population size 20–90KYA, before dispersing across the continent during the Holocene. In addition, we find strong evidence thatS. mansonimigrated to the New World with the 16–19thCentury Atlantic Slave Trade.