Genetic differentiation of pathogenic and nonpathogenic strains of Entamoeba histolytica by random amplified polymorphic DNA polymerase chain reaction.

The random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) method was used to compare pathogenic and nonpathogenic strains of Entamoeba histolytica. DNA polymorphisms were detected among the different strains and dendrograms were constructed by PHYLIP and PAUP analyses to study the relationship of the strains. Both analyses resulted in identical results, which indicated that pathogenic strains of E. histolytica are closely related and clearly separated from the nonpathogenic strains. The results of this study agree with classification of the strains based on isoenzyme analyses. This suggests that RAPD-PCR is a valuable method in differentiating between strains of this parasite, and the results are consistent with the concept that pathogenic and nonpathogenic Entamoeba represent two different species.