Isolation and Genotyping of Toxoplasma gondii Strains.

Toxoplasma gondii is a protozoan parasite that infects mammals and birds. Molecular epidemiology and population genetic studies have revealed widespread and distinct distribution of different T. gondii genotypes globally. Animals (domestic and wild) are the reservoirs for transmission of this parasite to humans. Recent development in molecular genotyping methods allowed us to identify parasite strains with high resolution and to dissect transmission patterns among different hosts. However, current data in the literature is still limited and fragmented. Here, we summarize a set of protocols that can be used to identify T. gondii infection in clinically normal animals, isolate the parasite by bioassay using animal tissues, extract parasite DNA from tissue samples, and finally identify the parasite by multilocus PCR-RFLP genotyping. We hope these protocols provide essential tools to study genetic diversity, population structure and transmission dynamics of T. gondii. Accumulation of the information will allow us to better understand, control, and prevent T. gondii infection in the future.