Genotyping of trypanosoma cruzi from clinical samples by multilocus conventional PCR

Abstract

By the most recent nomenclature, Trypanosoma cruzi isolates are classified into six discrete typing units (DTUs)—T. cruzi I to T. cruzi VI and TcBat. One of the major challenges in the Chagas disease study is to find an association between DTUs and clinical manifestations of the disease or response to treatment. Herein, a protocol based on the amplification of T. cruzi SL-IRac, SL-IR I and II, 24Sα rDNA, and A10 targets by multilocus conventional PCRs is described. Following this methodology, it is possible to perform the genotyping directly from the blood and other clinical samples, without the need to isolate the parasite prior to the DNA extraction, even in a lower parasite concentration. Furthermore, this methodology increases the probability to detect mixed infections, avoiding a possible selection of strains during the parasite isolation.