Author(s): ALISON L VAN EENENNAAM
The first genetically engineered fish were produced 20 years ago, and since that time over 35 species have been genetically engineered. Currently, no genetically engineered fish has been approved for food production in the United States. Compared with mammals, fish offer important advantages for genetic engineering because of the large number of eggs laid per female, out-of-mother fertilization and embryonic develop - ment in most species, lower probability of carrying human pathogens, and the fact that aquaculture is a rapidly expanding market. Many countries, including China, Cuba, India, Korea, the Philippines, and Thailand, have active research programs in the area of genetically engineered fish. Ironically, in addition to being the taxonomic group with the most genetically engineered species, aquatic organisms are also one of the groups most likely to present environmental concerns if accidentally released into the environment. Unlike most other agricultural species, fish are difficult to contain and highly mobile, and they can easily become feral and invade native ecosystems (National Research Council 2002).