Application of transgenic animals in animal production and health

The progress in Recombinant DNA technology guided the way for production of transgenic plants and animals. The production of Bt cotton and Bt brinjal was one of them. Transgenic cows capable of producing human proinsulin and human lactoferrin in milk have been successfully engineered. Though the efficacy of the techniques used or such transgenic organism is questionable, with the creation of new and better technology like the clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein system, the chances and effectiveness for success of gene incorporation during development of a transgenic animal has increased. In near future such transgenics are going to play an important role in support and sustenance of human society. This review deals with the application of transgenesis for enhancing productivity and promoting better health in animals and humans alike.

A universal vector concept for a direct genotyping of transgenic organisms and a systematic creation of homozygous lines

Diploid transgenic organisms are either hemi- or homozygous. Genetic assays are, therefore, required to identify the genotype. Our AGameOfClones vector concept uses two clearly distinguishable transformation markers embedded in interweaved, but incompatible Lox site pairs. Cre-mediated recombination leads to hemizygous individuals that carry only one marker. In the following generation, heterozygous descendants are identified by the presence of both markers and produce homozygous progeny that are selected by the lack of one marker. We prove our concept in Tribolium castaneum by systematically creating multiple functional homozygous transgenic lines suitable for long-term fluorescence live imaging. Our approach saves resources and simplifies transgenic organism handling. Since the concept relies on the universal Cre-Lox system, it is expected to work in all diploid model organisms, for example, insects, zebrafish, rodents and plants. With appropriate adaptions, it can be used in knock-out assays to preselect homozygous individuals and thus minimize the number of wasted animals.