Molecular genotyping of Anisakis species from Korean sea fish by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)

The anisakid nematode is a prevalent foodborne pathogen that causes gastroenteritis in humans. The aim of this study was to identify the molecular genotype of Anisakis worms found in Korean sea fish and squid. Sixty DNA samples were prepared from third stage larvae of Anisakis spp. collected from Scomber japonicus, Trichiurus lepturus, and Todarodes pacificus. An approximately 1000 base pair fragment in the internal transcribed spacer (ITS) regions, including ITS-1, ITS-2, and the 5.8S subunit, was amplified and digested with HinfI or HhaI. We identified restriction fragment length polymorphism patterns of Anisakis pegreffii, Anisakis simplex sensu stricto, Anisakis typica, and a hybrid genotype. Among the 60 isolates, 47 were identified as A. pegreffii, 10 as A. typica, one as A. simplex sensu stricto, and two as hybrid genotypes. A. pegreffii was determined to be the most prevalent molecular genotype of A. simplex complex found in Korean sea fish.