[Genetic variability of Trichinella spiralis Oven, 1835, and Trichinella pseudospiralis Garkavi, 1972, detected by polymerase chain reaction with random primers].

DNA polymorphisms in two parasitic nematode species, Trichinella spiralis Oven, 1835, and Trichinella pseudospiralis Garkavi, 1972, were revealed via random amplification of polymorphic DNA by the polymerase chain reaction (RAPD PCR). The diagnostic value of seven 10-bp oligonucleotide primers was evaluated, and the extent of the homology between the genomes of the two species was estimated. The intraspecific variation of RAPD markers was revealed in larvae of both species isolated from experimentally infected white rats. The variation was higher in larvae from nonlinear rats than in larvae from linear rats. When animals were infected with both Trichinella species simultaneously, "hybrid" progeny were obtained that had capsule that somewhat differed in shape from one characteristic of the parental species, T. spiralis. In RAPD spectra, the hybrids showed higher similarity of T. spiralis than to T. pseudospiralis. Intra- and interspecific differentiation, genome divergence, and factors inducing the intraspecific variation in Trichinella species are discussed.