Trans Sialidase Genes Allow Clustering of TcI Trypanosoma cruzi Mexican Isolates

Aims: Polymorphism of the trans sialidase (TS) family of genes is common in Trypanosoma cruzi. Our goal was to cluster Mexican TcI DTU (Discrete Typing Unit) using a set of primers specific for TS genes.

Methodology: The DNA of 12 Mexican T. cruzi stocks (TcI) and reference strain were amplified using the CRP-1 primer, which anneals to the conserved 5' ends of CRP (Complement Regulatory Protein), TS, and FL-160 genes, and the CRP-2 primer, which anneals to conserved region within the GPI (Glycosil Phosphatidil Inositol) anchor sequence. Amplicons were analysed using PCR-SSCP (Single Strand Conformation Polymorphims) followed by construction of a nominal matrix data (presence/absence bands) to calculated the Jaccard and Dice similarity coefficient, and clustering with UPGMA.

Results: Mexican TcI stocks produced a common pattern of amplification products and cluster in a separate group to CL-Brener strain (TcVI). The PCR-SSCP revealed that within the TcI Mexican stocks there were a complex pattern, but T. cruzi from the Yucatan peninsula clustered in special and separate group.

Conclusion: The CRP-1 and CRP-2 primers were helpful for the analysis of genetic traits in T. cruzi DTU I and revealed the existence of special group in Yucatan Mexico.