STATUS OF DEVELOPMENT OF TRANSGENIC AQUATIC ANIMALS

Atlantic salmon expressing a growth hormone (GH) transgene may become the first genetically engineered animal approved for commercial food production1. With 4–6 times the growth rate and a 10–20 % improvement in feed conversion efficiency relative to non-transgenic salmon, production of the transgenic line offers shorter production times, reduced costs, and improved profitability to aquaculturists2. However, the transgenic salmon also pose food safety and environmental concerns3-5. With other transgenic fish likely to enter the regulatory system within the foreseeable future, a review of issues posed by development of transgenic aquatic species is timely. Scope of research and development effort The AquaBounty Atlantic salmon is the most widely publicized example of a large international effort aimed at developing transgenic aquatic and marine organisms (Table 1). The most frequent application is for food production; GH genes have been inserted into over a dozen species4. Cecropin6, interferon, and other genes have been introduced to increase non-specific immunity to disease. Transgenic zebrafish, medaka, and other species are used as model systems for research on gene expression and embryological development. In a recent applica-tion, tilapia were engineered for use as bioreactors to express human coagulation factor VII in their blood7. Transgenic fish are under development for environmental biomonitoring, for example, for detecting environ