Identity-by-descent with uncertainty characterises connectivity of < i > Plasmodium falciparum < /i > populations on the Colombian-Pacific coast

by Aimee R. Taylor, Diego F. Echeverry, Timothy J. C. Anderson, Daniel E. Neafsey, Caroline O. Buckee Characterising connectivity between geographically separated biological populations is a common goal in many fields. Recent approaches to understanding connectivity between malaria parasite populations, with implications for disease control efforts, have used estimates of relatedness based on iden tity-by-descent (IBD). However, uncertainty around estimated relatedness has not been accounted for. IBD-based relatedness estimates with uncertainty were computed for pairs of monoclonalPlasmodium falciparum samples collected from five cities on the Colombian-Pacific coast where long-term clonal propagation ofP. falciparum is frequent. The cities include two official ports, Buenaventura and Tumaco, that are separated geographically but connected by frequent marine traffic. Fractions of highly-related sample pairs (whose classification using a threshold accounts for uncertainty) were greater within cities versus between. However, based on both highly-related fractions and on a threshold-free approach (Wasserstein distances between parasite populations) connectivity between Buenaventura and Tumaco was disproportionally high. Buenaventura-Tumaco connectivity was consistent with transmission events involving parasites from five clonal components (groups of statistically indistinguishable parasites identified under a graph theoretic framework). To conclude,P. falciparum population conn...
Source: PLoS Genetics - Category: Genetics & Stem Cells Authors: Source Type: research