MOLECULAR KARYOTYPE AND SCHIZODEME ANALYSES OF TRYPANOSOMA-CRUZI STOCKS FROM CHILEAN TRIATOMINES

Forty-one Trypanosoma cruzi stocks isolated from the Chilean vectors T riatoma infestans and Triatoma spinolai were characterized by pulse-fi eld gel electrophoresis and Southern blotting with the cruzipain gene, and by schizodeme analysis of kinetoplast DNA. with EcoRI and Msp I. Seven parasite groups were found by molecular karyotype which correlat e with schizodeme and multilocus enzyme electrophoresis, supporting th e concept of clonal propagation for Trypanosoma cruzi. A predominant T . cruzi stock was isolated from domiciliary T. infestans in several ge ographical areas of Chile. In contrast, other frequently found genotyp es were circulating in the sylvatic and domestic transmission cycles o f specific geographical areas. The greatest heterogeneity of T. cruzi stocks was found among sylvatic T. spinolai where at least 4 genotypes were obtained from a sample of 16 T. cruzi stocks.