1Groundfish Biology Section, Subarctic Fisheries Resources Division, Hokkaido National Fisheries Research Institute, Kushiro, Hokkaido 085-0802, 2Laboratory of Environmental Biology, Japan NUS Co., Ltd., Minato, Tokyo 108-0022, Japan
Mitochondrial DNA sequences of the cytochrome b gene (1161bp) were obtained from three gadoid species (Theragra chalcogramma, Gadus macrocephalus, and Eleginus gracilis) near Hokkaido, Japan. Four restriction enzymes (DpnII, HaeIII, RsaI and TaqI) were diagnostic to identify these three species. Species—specific internal primers were designed based upon the characteristic nucleotide substitutions in each species, which allowed discrimination among these three species by amplicon size.