Information about cloning technology for the benefit of mankind

Benefits:1) Cloning technology can relieve the pain of women who cannot become mothers. 2) The implementation of cloning experiments has contributed to the development of genetics. 2) The implementation of cloning experiments has facilitated the development of genetics and opened up the prospect of "making" animal organs that can be transplanted into human beings. 3) Cloning can also be used to detect genetic defects in fetuses. Fertilized eggs are cloned for the detection of various genetic diseases, and the cloned embryos are genetically identical to the fetus developing in the womb. 4) Cloning can be used to treat damage to the nervous system. Nervous tissue in adults does not have the ability to regenerate, but stem cells can repair neurological damage. 5) In an in vitro fertilization procedure, doctors often need to implant multiple fertilized eggs into the uterus in order to screen one of them for the pregnancy stage. However, many women can only provide one egg for fertilization. This problem can be well solved by cloning. This egg cell can be cloned into more than one for fertilization, thus greatly increasing the success rate of pregnancy. Cloning technology has demonstrated broad application prospects, which are summarized in the following four areas: (1) breeding of superior livestock breeds and production of experimental animals; (2) production of transgenic animals; (3) production of human embryonic stem cells for cell and tissue replacement therapy; and (4) replication of endangered animal species, preservation and dissemination of animal species resources. A brief description of the production of transgenic animals and embryonic stem cells follows. Transgenic animal research is one of the most attractive and promising topics in the field of animal bioengineering. Transgenic animals can be used as donors for medical organ transplants, as bioreactors, and for genetic improvement of livestock, creation of experimental models of diseases, and so on. However, at present, the practical application of transgenic animals is not much, in addition to a single gene modification of transgenic mice medical model has been applied earlier, transgenic animal mammary gland bioreactor production of drug proteins in the research of a longer period of time, has been carried out for more than 10 years, but at present in the world only 2 cases of drugs into the phase 3 clinical trials, 5 to 6 drugs into the phase 2 clinical trials; and its agronomic traits have been improved, can be funded No transgenic livestock lines with improved agronomic traits that can be used in livestock production have been born so far. The low production efficiency of transgenic animals, the high cost and regulatory failure caused by the difficulty of targeted integration, and the separation of genetic traits in the sexually reproduced offspring of transgenic animals, which makes it difficult to maintain the excellent traits of the progenitor, are the main reasons restricting the process of the practical application of transgenic animals nowadays. The success of somatic cell cloning has revolutionized the production of transgenic animals, and the technique of somatic cell cloning provides a technical possibility to rapidly amplify the germplasm innovation effect produced by transgenic animals. The use of a simple somatic cell transfection technique to implement the transfer of target genes can avoid the difficulty and inefficiency of sourcing germ cells from domestic animals. Meanwhile, the use of transgenic somatic cell lines allows pre-testing for transgene integration and pre-selection for sex under laboratory conditions. Before nuclear transfer, the fusion gene of the target exogenous gene and marker genes (e.g., LagZ gene and neomycin resistance gene) is introduced into cultured somatic cells, and then the transgene-positive cells and their clones are screened by the performance of the marker genes, and then the nucleus of this positive cell is transplanted into denucleated oocytes, and the final animals produced should theoretically be 100% positive transgenic animals. Using this method, Schnieke et al. (Bio Report, 1997) have successfully obtained 6 transgenic sheep, of which 3 with the human coagulation factor IX gene and marker gene (neomycin resistance gene), and 3 with the marker gene, with the integration rate of the target exogenous gene as high as 50%.Cibelli (Science, 1997) has similarly obtained 3 transgenic cows by using nuclear transplantation, confirming the method. Cibelli (Science, 1997) also utilized the nuclear transfer method to obtain three transgenic cattle, confirming the effectiveness of the method. It can be seen that one of the most important application directions of animal cloning technology today is the research and development of high value-added transgenic cloned animals. Embryonic stem (ES) cells are totipotent stem cells with the potential to form all adult cell types. Scientists have been trying to induce various stem cells to differentiate directionally into specific tissue types to replace those damaged body tissues, such as implanting insulin-producing cells into diabetic patients. Scientists have been able to transform porcine ES cells into beating heart muscle cells, human ES cells into neuronal and mesenchymal cells and mouse ES cells into endodermal cells. These results open the way for cell and tissue replacement therapies. Currently, scientists have succeeded in isolating human ES cells (Thomson et al. 1998, Science), and somatic cell cloning techniques offer the possibility of producing a patient's own ES cells. The patient's somatic cells are transplanted into enucleated oocytes to form a recombinant embryo, the recombinant embryo is cultured in vitro to a blastocyst, from which ES cells are then isolated, and the ES cells obtained are made to differentiate directionally into the specific cell types required (e.g., nerve cells, muscle cells, and blood cells) for use in alternative therapies. The ultimate goal of this nuclear transfer method is to use the cells for stem cell therapy rather than to obtain a cloned individual, which scientists refer to as a "therapeutic clone". The application of cloning technology in basic research is also of great interest, as it provides tools for studying mechanisms of gametogenesis and embryogenesis, cell and tissue differentiation, regulation of gene expression, and nucleoplasmic interactions. Thanks hope my answer is useful to you