Whole-genome sequencing describes recombination in Toxoplasma and identifies loci that determine fitness and avoidance of outcrossing. Toxoplasma gondii BOF

Toxoplasma gondii is a highly successful protozoan parasite that infects all warm-blooded animals and causes severe disease in the immunocompromised and immune-naive. It has an unusual global population structure: in North America and Europe isolates fall predominantly into three largely clonal lineages while in South America there is great diversity and the clonal lineages are rarely found. Genetic variation between Toxoplasma strains determines strain differences in virulence, modulation of host signaling pathways, growth, dissemination and disease severity in mice and possibly in humans. Most studies on Toxoplasma genetic variation focus on a few loci for many strains or low resolution genome analysis of the clonal lineages. Using whole genome sequencing we identified more than a million SNPs between ten Toxoplasma strains from Europe, North and South America. These were used to construct a Toxoplasma haplotype map and track the genealogy for each haplotype block.