Development of HAT-RAPD marker for detection of Stellantchasmus falcatus infection.

The trematode, Stellantchasmus falcatus, is one of the members in the Family Heterophyidae, which is reported to be an endemic fluke in northern region of Thailand. A sensitive and specific detection of this parasite is required to determine the epidemiology at larval stages. Specific primers to determine the presence of S. falcatus were investigated using high annealing temperature random amplified polymorphic DNA (HAT-RAPD) PCR, with 10 arbitrary primers to generate different polymorphic DNA profiles. Eleven parasite species were used for comparison. A 380 bp HAT-RAPD S. falcatus-specific marker was found, and was cloned and sequenced, allowing a pair of primers (St-F 5'-GGCCAACG CAATCGTCATCC-3' and St-R 5'-GCGTCGGGTTTCAGACATGG- 3') to be designed to produce a 320 bp amplicon specific for S. falcatus. It revealed no cross-reaction with any of the other tested parasite species. The S. falcatus-specific primers can be used for epidemiological monitoring and for detection in snail intermediate hosts, which serve as usefulness tools in management and epidemiological control programs.