First genetic characterization of Fasciola hepatica in Argentina by nuclear and mitochondrial gene markers.

Fasciola hepatica is a trematode showing genetic variation among isolates from different regions of the world. The objective of this work was to characterize for the first time F. hepatica isolates circulating in different regions of Argentina. Twenty-two adult flukes were collected from naturally infected bovine livers in different areas from Argentina and used for DNA extraction. We carried out PCR amplification and sequence analysis of the ribosomal internal transcribed spacer 1 (ITS1), mitochondrial nicotinamide adenine dinucleotide dehydrogenase subunits 4 and 5 ( nad 4 and nad 5) and mitochondrial cytochrome c oxidase subunit I ( cox 1) genes as genetic markers. Phylogenies were reconstructed using maximum parsimony algorithm. A total of 6 haplotypes were found for cox 1, 4 haplotypes for nad 4 and 3 haplotypes for nad 5. The sequenced ITS1 fragment was identical in all samples. The analyzed cox 1 gene fragment is the most variable marker and is recommended for future analyses. No geographic association was found in the Argentinean samples. [ABSTRACT FROM AUTHOR]