1Laboratory of Environmental Biology, Japan NUS Co., Ltd., Tokyo 108-0022, 2Kanagawa Prefectural Yokosuka-Miura Area Agriculture Office, Kanagawa 238-0006, 3Kanagawa Prefectural Fisheries Institute, Kanagawa 238-0237, 4Department of Fisheries, School of Marine Science and Technology, Tokai University, Shizuoka 424-8610, 5Laboratory of Aquatic Molecular Biology and Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
Mitochondrial cytochrome b genes were amplified by PCR using the total DNA as a template from muscle tissues of adult chub mackerel Scomber japonicus and spotted mackerel S. australasicus, and their nucleotide sequences determined. The full length of the cytochrome b gene consisted of 1,140 nucleotides irrespective of the two species, where 16 species-specific variations were observed. Among various restriction enzymes which recognize the cytochrome b genes from the two fish species, MvaI was specific to the gene of S. japonicus and MboI to that of S. australasicus, with both enzymes producing two fragments. Such species-specific fragmentation patterns were applicable to identification of formalin-fixed pelagic eggs from the two species, which was impossible with morphological characteristics.