T. vaginalis population structure based on 19 Tvmar1 insertions. (A) Principal component analysis (PCA) using seven geographical groups. A shape represents each isolate and color represents genetic type 1 and 2. The first three PCA axes explain the highest percentage of the variation (60.81% first, 18.94% second and 10.53% third). (B) Structure analysis of T. vaginalis isolates using K = 2, determined as the optimal K number. Each individual is represented by a thin vertical line, which is partitioned into K segments that represent its estimated population group membership fractions. Black lines separate groups of isolates. AUS, Australia; ITA, Italy; LST, laboratory strains; MEX, Mexico; PCA, principal component analysis; PNG, Papua New Guinea; SAF, South Africa; USA, United Sates of America.