Genetic diversity of Fasciola hepatica in Spain and Peru.

In the present study, molecular characterization of Fasciola flukes from Spain was performed to reveal the relation with the previously reported Peruvian F. hepatica population. The nuclear DNA markers, phosphoenolpyruvate carboxykinase (pepck) and DNA polymerase delta (pold), were used for species identification of Fasciola flukes. A total of 196 Fasciola flukes were identified as F. hepatica by pepck and pold, and 26 haplotypes were detected in mitochondrial NADH dehydrogenase subunit 1 (nad1). Only one of them was previously found in Spanish samples; which indicates the existence of high genetic diversity and population structure in F. hepatica from Spain. Three haplotypes were identical to those from Peruvian F. hepatica. The pairwise fixation index value confirmed a relatively close relationship between the Spanish and Peruvian F. hepatica samples. The Spanish samples showed clearly higher genetic variability than the Peruvian population. These results are discussed in relation with the hypothesis of the introduction of the parasite in America from Europe and recent evidence of pre-Hispanic F. hepatica from Argentina revealed by ancient DNA.