Transgenesis is the revolutionary science of making a genetically modified organism. Interestingly, fish offer easier genetic manipulation compared to mammalian counterpart, as they bred easily and large number of eggs is laid by female (higher fecundity) and have independent embryonic biology. The primary goals for genetic manipulation of fish species used in aquaculture are to: a) Intensify the growth and efficiency of food conservation, b) Increase tolerance to environmental variables, such as temperature and salinity, c) Bring out new color variants of ornamental fishes, and d) Develop disease resistant forms. The different approaches for transgenic fish production have been practiced, each having advantages and disadvantages demanding further improvements. Although selective breeding technology has demonstrated its impact on fish production, it is a time-consuming; whereas genetic improvement by direct gene manipulation of transgenic approach could be accomplished inside a span of years. Therefore, both the traditional selective breeding and transgenic approaches are required to supplement dramatically heightened future food requirements because of the growth in human population. We have likewise concentrated on strategies towards value-addition to ornamental fishes by developing novel color variants. With the huge variety of fishes, transgenesis could be useful for bringing forward a new color form of ornamental species and to control reproductive performance or sexual phenotype. The ecological, ethical and biosafety issues associated with transgenic fishes are discussed. The suitable techniques being used to produce transgenic fishes are also discussed. Concerns associated with the stability of the introduced transgenes in fishes vis-a-vis future perspectives have been deliberate.
Kiran Dashrath Rasal, Vemulawada Chakrapani, Swagat Kumar Patra, Arun S Ninawe, Jitendra Kumar Sundaray, Pallipuram Jayasankar and Hirak Kumar Barman*