Genetic variation within Pseudoterranova decipiens (Nematoda: Ascaridoidea) from Canadian Atlantic marine fishes and seals: Characterization by RFLP analysis of genomic DNA

作者：Brattey J^*; Davidson WS

来源：Canadian Journal of Fisheries and Aquatic Sciences, 1996, 53(2): 333-341.

DOI：10.1139/cjfas-53-2-333

Genetic variation in the ribosomal RNA gene complex (rDNA) of 181 individual Pseudoterranova decipiens from three seal species and six marine fish species collected widely throughout Atlantic Canada was investigated by restriction endonuclease digestion followed by Southern blotting using a heterologous cloned rDNA repeating unit as a probe. Five enzymes (EcoRI, HaeII, HpaI, PstI, PvuII) yielded informative restriction fragment length polymorphisms and the results, which corroborate previous studies of allozyme variation, indicate two species with no evidence of hybridization or introgression between them: one species (= P. decipiens C) infects bearded seals, Erignathus barbatus, and is characterized by six unique restriction fragments; the other (= P. decipiens B) infects both harbour seals, Phoca vitulina, and grey seals, Halichoerus grypus, and is characterized by 10 unique restriction fragments. Larvae from most areas throughout Atlantic Canada showed restriction fragment length polymorphisms characteristic of P. decipiens B, but some specimens collected from flatfishes off Labrador were P. decipiens C. Restriction fragment patterns also revealed polymorphism, both within and between species, and among ribosomal repeat units within individuals, particularly within P. decipiens B. The genetic polymorphisms observed in P. decipiens from grey and harbour seals were similar, suggesting interbreeding among nematodes from these two pinniped species.

• 出版日期1996-2