PRODUCTION OF GERMLINE TRANSGENIC PACIFIC SALMONIDS WITH DRAMATICALLYINCREASED GROWTH-PERFORMANCE

Transgenic Pacific salmon have been produced by microinjection of a DN A construct consisting of chinook salmon (Oncorhynchus tshawytscha) gr owth hormone sequences driven by an ocean pout (Macrozoarces americanu s) antifreeze protein promoter. This construct was retained in approxi mately 4% of fish derived from injected eggs, and resulted in dramatic enhancement of growth relative to controls. For coho salmon (O. kisut ch) at 15 months of age, the average size of transgenic fish was more than 10-fold that of controls, with the largest fish more than 30-fold larger than nontransgenic siblings. Dramatic growth enhancement was a lso observed in transgenic rainbow trout (0. mykiss), cutthroat trout (0. clarki), and chinook salmon using this same gene construct. Transg enic coho salmon underwent precocious parr-smelt transformation during their first fall, approximately 6 months in advance of their nontrans genic siblings. At 2 years of age, five male transgenic coho salmon be came sexually mature, and four of these transmitted the gene construct to sperm, the negative fish being transgenic in blood but not fin tis sue. These results show that while some fish are mosaic for the gene c onstruct in different tissues, most are transgenic in both germline an d somatic tissue.