High similarity of Trypanosoma cruzi kDNA genetic profiles detected by LSSP-PCR within family groups in an endemic area of Chagas disease in Brazil.

Introduction: Determining the genetic similarities among Trypanosoma cruzi populations isolated from different hosts and vectors is very important to clarify the epidemiology of Chagas disease. Methods: An epidemiological study was conducted in a Brazilian endemic area for Chagas disease, including 76 chronic chagasic individuals (96.1% with an indeterminate form; 46.1% with positive hemoculture). Results: T. cruzi I (TcI) was isolated from one child and TcII was found in the remaining (97.1%) subjects. Low-stringency single-specific-primer-polymerase chain reaction (LSSP-PCR) showed high heterogeneity among TcII populations (46% of shared bands); however, high similarities (80-100%) among pairs of mothers/children, siblings, or cousins were detected. Conclusions: LSSP-PCR showed potential for identifying similar parasite populations among individuals with close kinship in epidemiological studies of Chagas disease.