Size data for transgenic coho salmon from 5 rivers

<p>Experiments examining potential impacts of growth hormone (GH) transgenesis in fish typically use a single source strain, and do not address potential differential impacts in strains of different genetic backgrounds. Here, we examine the effects of differing genetic backgrounds on the growth of transgenic and non-transgenic coho salmon produced by mating sires from different rivers with transgenic dams from a single origin. We found a significant difference in size between offspring of sires originating from various river systems in British Columbia. This difference was independent of differences between transgenotypes (i.e., transgenic vs. non-transgenic offspring). However, the effects of strain or sire were relatively small compared to the effects of the transgene, which were consistent regardless of sire origin. Thus, results derived from studies of GH transgenic fish from a single source pouplation could provide useful information for assessments of GH transgenic salmon from other systems. This has important implications for examining potential risks from introgression of a transgene into different populations.</p>