What are Transgenic Animals?

The basic substance of inheritance is DNA, and genes are DNA fragments that have genetic effects on chromosomes. For all genetic information stored in a complete set of chromosomes in an organism, it can be called a genome. Because the genetic composition of different species and individuals is different, for animal individuals, non-self gene components are foreign genes. If foreign genes are integrated or introduced into animal chromosomal genes, then this foreign gene will be It is called transgene (transgenic gene), and this kind of animal is transgenic animal.

Animal models of disease have contributed to the development of medicine. However, many diseases are difficult to create animal models by artificially induced methods, or many diseases do not occur in experimental animals or are only advanced

Humans transform natural biological populations, starting with artificial selection and breeding, followed by artificial hybridization and artificial mutation. In 1983, Chinese scientist Zhu Zuoyan first developed transgenic fish successfully in the world. In the 1990s, transgenic sheep were successfully developed in China. ^[4]

Transgenic avian bioreactor, including liver and fallopian tube expression systems. In 1993, Dr. Sang of the Ruslin Institute successfully expressed foreign proteins in the yolk of avian eggs. From 1994 to 1995, Zeng Bangzhe of China proposed the system genetics method and pioneered the concept, terminology, and vocabulary of the oviduct bioreactor-the Gold Egg Plan for genetically modified birds. The 1st International Symposium on Genetically Modified Animals (Secretary-General Zeng Bangzhe) was held in Beijing in 1996 and explained (Zeng BJ) the fallopian tube bioreactor, biosystem theory and genetics, and bioengineering. With the participation and support of well-known Chinese scientists such as Liu Depei, mammalian mammary gland bioreactors and avian fallopian tube bioreactors have become important directions for genetically modified animals.

Animal cloning-asexual reproduction technology, started in 1938 by German scientist Speyman's fertilized egg ligation experiment. In 1961, the Chinese scientist Zhu Xi successfully used artificial stimulation of toad mature eggs to successfully study the artificial parthenogenesis of amphibians. In 1962, British scientist JB Gurdon successfully cultivated Xenopus adult using nuclear transfer. In 1980, American biologist PC Hoppe and Geneva micro-surgery expert KI Illmense successfully bred mice using blastocyst nuclear transfer.

In 1997, British I. Wilmut et al. Used the nucleus of sheep mammary gland cells to transplant nucleated egg cells and successfully obtained the cloned sheep "Dolly". The main purpose of cloning animals was to solve the problem of transgenic animal strains used as bioreactors. Purebred breeding issues.

In the 21st century, genetic engineering based on systems biology-synthetic biology, that is, the progress of systems bioengineering technology, transgenic technology includes research and development of transgenic animals, and has entered the transgenic system biotechnology of artificial design, synthesis of genes and gene regulatory chains The new era has changed the previous methods of single gene cloning, vector construction and gene transfer, and opened the era of multi-gene transgenic biotechnology, which includes whole gene synthesis, gene regulatory network design, and artificial genome transfer.