한국 바다와 인근해에서 일어나는 몇가지 어류의 집단 구조 및 유전적 흐름 분석

Abstract

We have examined population structures and gene flows of three fish species showing distinctive distribution patterns in Korean waters in connection with other oceans. Maurolicus japonicus (North Pacific lightfish) is a small (4-7 cm long) mesopelagic fish having two distant populations, one in the southern part of the East Sea and the other in the Southwest Atlantic and the West Indian Ocean. Analysis of 16SrDNA haplotype frequency of the two populations with the isolation with migration model (IM) reveals that they seemed to split about 350,000 years ago and migration occurred unidirectionally from the Southwest Atlantic to the East Sea approximately 128,000 years ago (the mean time of all migration events). Nested clade phylogeographic analysis (NCPA) supports the restricted gene flow between the two populations. Oncorhynchus keta (chum salmon) is an anadromous fish widely distributed in the North Pacific. Pairwise Fst and AMOVA analyses of populations along the coast of the North Pacific with COIII-ND3-ND4L sequences distinguish three genetic units, a Korea-Japan unit, a Russia(including east Sakhalin)-Alaska-Canada unit, and a Washington (USA) unit. Hexagrammos otakii (fat greenling) is a demersal fish occurring in the Northwest Pacific, the East Sea, and the Yellow Sea. Genetic analyses of the populations from the three places show that their haplotype diversities are relatively high in contrast to the low nucleotide diversity and that they have experienced population bottleneck and rapid expansion resulting in the current absence of genetic structure.