단염기다형성에 근거한 계군 특이적 PCR로써 연어의 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 for enrichment of the stocks. Since the released salmons migrate through EEZ of the neighboring countries and intermix in the open ocean, it becomes important to set up some criteria and methods discriminating each stock in order to clarify each nation's right of harvest of the salmon resources. Here, we report a few stock-specific single nucleotide polymorphisms (SNPs) in the COIII-ND3-ND4L region of the mitochondrial DNA and present a simple method of stock separation by polymerase chain reaction(PCR) utilizing the SNPs. A total of 141 chum salmons from Korea, Japan, Canada, and the United States were analyzed and 744 nucleotide sequences of the COIII-ND3-ND4L region were compared each other in this study. Several SNPs were observed in the region, some of which were stock-specific (e.g., positions 57, 70, 246, 303, 307, 534, 591). Based on these SNPs, 20-25 nucleotide long stock-specific PCR primers were designed so that a single PCR with these primers could discriminate salmon stocks among Korea, Japan, Canada and the United States. The primers have the most 3'end nucleotide identical to the SNPs and the second to the 3'end being a mismatch to any of the sequences. With such primer design, a PCR with SF0 (a primer of a conserved sequence) and SR1 (a primer with Korea stock-specific SNP) amplified DNA only from the Korea salmons. This study suggests that SNPs in the COIII-ND3-ND4L region would be useful genetic markers for stock separation and PCR with the modified primers utilizing the SNPs provide a simple method for such purpose.