유전적 형질에 의한 북태평양 연어 (Oncorhynchus keta)의 계군 구분

Abstract

The chum salmon (Oncorhynchus keta) is an anadromous fish distributed all around the North Pacific. Artificial production and release of the juveniles are being made by Korea, Japan, Russia, Canada and the United States. It is important to set up some criteria identifying each stock in order to clarify each nation's right of harvest for the chum salmon resource. As an attempt to build such criteria, we analyzed sequences of a microsatellite DNA Ogo5 and the COIII-ND3-ND4L region of the mitochondrial DNA from chum salmons of Korea, Japan, and the United States. Ogo5 has 4 different alleles: allele A, B-1, B-2, and B-3. Allele B-3 is found only in 3 individuals out of 12 Korea salmons. The Japan salmons have the other 3 alleles and the America salmons have only 2 allots, A and B-1. Heterozygosity index (Ho/He) distinguishes the Korea (1.61) and Japan salmons (1.63) from the America ones (1.09). Seventeen different haplotypes are found in the COIII-ND3-ND4L region from 60 individuals,20 from each stock. The gene genealogy of the haplotypes revealed by TCS program shows that the Korea and Japan salmons are genetically closely linked, but that they are clearly distinguished from the America ones. Ten and eleven individuals of the Korea and Japan salmons have an identical haplotype. Nine individuals of the Korea salmons (45%), however, are separable from the Japan salmons by their own specific nucleotides. This result presents usefulness of the COIII-ND3-ND4L region as a genetic marker for identification of the chum salmon stocks.