DNA-FINGERPRINTING AND CLONING OF HYPERVARIABLE MINISATELLITE REPEATSIN SALMONIDS

We used heterologous jeffreys' 33.6 core sequence and microsatellites (CAC)(5) and (CA)(12) as probes and compared them with probes based on the minisatellite sequences from tilapia (Oreochromis niloticus) and Atlantic salmon (Salmo salar) in fingerprinting assays. DNA fingerprin ts generated with the Jeffreys' 33.6 core sequence and the microsatell ite (CAC)(5) and (CA)(12) probes showed complex profiles with high bac kground, but DNA fingerprints using the tilapia and Atlantic salmon pr obes showed clear, less complex, informative, individual-specific DNA fingerprints suitable for analysis. We cloned and sequenced homologous repetitive sequences using a novel approach of creating a chinook sal mon (Oncorhynchus tshawytscha) genomic DNA library with enriched low C (0)t DNA repeats for the development of DNA probes. The four types of repeats identified and sequenced were (CT)(n) and three Alu-like seque nces. We generated DNA fingerprints using one of the minisatellite seq uences as a probe. This minisatellite sequence was shown to be species specific because it is abundant in chinook and coho salmon (Oncorhync hus kisutch) genomes, but not in Atlantic salmon. These probes will pr ovide us with the tools to study pedigree and linkage analysis, patern ity testing, breeding programs, and the analysis of genetic structure within populations for aquaculture and fisheries research.