Transgenic technology and its potential social problems (1)

Introduction: 1 The meaning and application of transgenic technology (1) what is transgenic technology? The rapid development of modern bioengineering technology has been widely used in agricultural production, food processing and other fields, resulting in the generation of genetic products This product is to change the gene of biological tissue by using gene enhancement technology, so that animals and plants get more functions than natural selection and artificial breeding, with high quality and high yield characteristics There are generally two ways to change genes: one is to use bioengineering technology in the same species, so that it can effectively, accurately and quickly obtain the functions obtained by scientific breeding That is to speed up the process of biological natural production For example, adding appropriate hormones in the breeding of chickens, cattle and other animals can promote the production and development of animals and increase the output of milk, meat and eggs There is no gene transfer between different species in this breeding method, and the genetic characteristics of species generally do not change The other is transgenic technology, which is related to the change of cell information That is to say, the target gene of one species is artificially implanted into the cell of another species, so that the original information of the implanted cell is partially changed, and the genetic characteristics of the implanted species are changed This process, also known as genetic engineering, technically allows the insertion of genes from one plant or animal into another For example, putting some genes of fish into tomatoes can prolong the storage period of tomatoes; adding genes of some bacteria into potatoes can improve their disease resistance, etc In the 1980s, the world's first genetically modified plant was born Up to now, there are about 40 million hectares of genetically modified crops, and genetically modified animals were born and a large number of medical proteins were produced using genetically modified bioreactors Human beings gradually applied the latest biotechnology to medicine, agriculture, food processing industry and other industries, and the development of genetically modified technology is very rapid （2） The application of transgenic technology 1 The great achievements of transgenic technology in agriculture and food industry At first, transgenic technology was used to solve the problem of food consumption for the growing population of the earth Later, it was found that it can also cultivate high-quality, high-yield, drought resistant, waterlogging resistant, cold resistant, disease resistant and insect resistant crop varieties For example, the amino acid content of corn cultivated by transgenic technology is 70% higher than that of corn cultivated normally And it can produce vaccines for poultry and livestock, which has great application potential and has attracted great attention from all countries Many countries in the world have formulated their own unique development plans for bioengineering technology The United States is the largest investor in the research and development of genetically modified technology Its soybean and corn cultivated by genetically modified technology have high yield In 1997, 15% of soybean production in the United States was genetically modified In 1999, USAD said that 30% of corn planted in the United States was genetically modified, 27% of cotton was genetically modified, and 57% of soybean was herbicide resistant, most of which were roundup ready Genetically modified soybean and non genetically modified soybean are not only identical in appearance, but also cultivated in rotation in the field, without distinction in marketing and food processing About 60% of food products (including cheese, cereal breakfast, bread, ice cream, soy sauce and vegetable fiber meat) on the food shelves of supermarkets in the United States contain soybeans and genetic soybeans 2 The application prospect of transgenic technology in medical field is very attractive It is a new way for therapeutics to introduce genes into body tissues to prevent and treat many genetic and acquired diseases The amplified gene will provide a missing function, regulate immune response or initiate cell suicide in the presence of certain drugs In the past 10 years, more than 30 companies have conducted relevant research to fully pursue the commercial potential of gene therapy In addition, a large number of drug and biotechnology companies have established gene therapy divisions or plans Gene therapy will eventually be used to treat different diseases such as cancer, infectious diseases and neurodegenerative syndrome Despite a considerable number of clinical trials, the reported success has been limited The main obstacles to be overcome are: effective gene transfer and sustained expression of therapeutic genes in target cells Therapeutic genes can be introduced into cells via viral or non viral vectors Non viral gene transfer includes liposome mediated DNA transfer and DNA carried directly on ballistic metal particles Non viral vectors are relatively easy to manufacture, have no pathogenicity and are free of unexpected pollutants, but they are generally less efficient as transducers On the other hand, viral vectors have the ability to target a specific cell type and tissue The extensive research on vector virology has constructed a safer and more effective vector The generation and purification of viral vectors are critical to the progress of gene therapy and clinical trials The need for a large number of highly purified viral vectors will increase dramatically with the increase of the number of diseases, so will the number of patients who can benefit from gene therapy based treatment In addition, the low production cost of viral vectors will make gene therapy more close to patients 3 The application of genetically modified technology in the field of biopharmaceutical industry Experts have predicted that the annual growth of the biotechnology drug market in the United States will reach 13% in 2006, and that of the biotechnology drug market in Europe from 1995 to 2002 will reach 8.5% This growth rate is much higher than the growth rate of other general product markets, so it attracts many investors The biotechnology industry is the latest industry, which has a huge impact on the healthcare market, but it does not mean that every company will succeed There may be a great risk in investing in the biotechnology industry If a biotechnology company's drug clinic is frustrated or the competent unit makes an adverse decision on the new drug applied for by the company, its share price will surely plummet, and the shareholders must understand the complex content of the latest scientific research The golden age of biotechnology industry began to come to an end At the beginning of 2000, many countries rushed into the craze of gene map decoding At that time, gene research stocks set new highs in succession But when investors realized that it would take several years for these companies to turn losses into wins, gene stocks fell from the cloud to the earth "Biotechnology is not a castle in the air," said Eric Lander, an American scientist who has been involved in the decoding of human genetic map "The research and development funds invested in it before will see results later When his child grows up, cancer will be more curable than it is now Celera Genomics (CRA) has completed the mapping of human gene map, and scientists believe that genome data will help new drugs develop a new era, which will lock in gene-induced diseases " 2、 The controversy on the application of transgenic technology because human beings use transgenic technology to transform biological genes, which goes far beyond the inherent laws of heredity and evolution in nature, and people can not predict the effect and change of these modified genes in a new genetic background Therefore, scientists worry that the new genetic genes and organisms created by the transgenic technology may pose a threat to human health and living environment So far, there is no clear answer about the potential threat of genetically modified products to human health and natural organisms, so there are many disputes in the application of genetically modified engineering in the international community （1） The United States is the first country to use transgenic technology in agricultural production Transgenic products in the United States agricultural production of 40% Many countries such as Europe, Canada and Australia are stepping up the research and commercial development of transgenic technology However, it is an indisputable fact that transgenic pollution caused by large-scale promotion of genetically engineered crops in the United States From planting to finished products, pollution may occur in almost every link Hybridization in the field is the original pollution, and the second pollution occurs in the uncleaned warehouse and transportation links, resulting in the seeds of traditional crops mixed with the seeds of genetic engineering crops The European Union and Japan's grain importers stipulate that the seeds of traditional crops imported from North America, of which no more than 0.1% are genetically modified, shall be regarded as qualified They seem to have no hope of getting absolutely pure traditional crop seeds
"Gene pollution" refers to the process that transgenes in genetically engineered crops can spread to other similar crops through the sexual reproduction process conducted by pollen (wind blown or insect borne), or spread to other cultivated crops or natural wild species through transgenic crops or domestic animals, and become a part of the latter gene, which is a process called "gene drift" in genetics In theory, gene drift is possible between almost all crops because of the existence of wild species and related species with sexual reproductive compatibility (copulability) in their distribution areas As a result of gene drift, some wild species may obtain new characters from transgenes, such as cold tolerance, disease resistance or fast growth, so they may have stronger vitality; or as another view holds, their vitality is weaker, because they have not gone through the process of natural selection No matter what kind of result, its harm is to affect the formed agricultural ecosystem and break the ecological balance of nature! This kind of pollution is undoubtedly harmful Traditional crops include a large number of varieties On their chromosomes, there are all kinds of genes of various characters needed by human beings They have been cultivated and selected by human beings for thousands of years, and they are a huge resource that can not be polluted There is no dispute that the genes of natural species can not be polluted The dispute is whether this kind of pollution will occur In fact, in recent years, it has been reported that the herbicide resistant genes of genetically engineered maize have drifted to the wild maize like plants in the vicinity, and the herbicide resistant genes of genetically engineered rape have drifted to the wild turnips in the vicinity Some resistant genes have been polluted by wild plants, which have resulted in the emergence of so-called "super weeds" Some genetically engineered organisms are particularly dangerous, such as transgenic fish and some transgenic invertebrates, as well as transgenic forests and transgenic algae, which have strong fecundity or release a large number of reproductive gametes to the outside world Genetically engineered Bt insecticidal crops continuously and uncontrollably produce large doses of Bt toxin protein, which can destroy pests on a large scale, but the insecticidal process can not be controlled, which may cause a sharp decline in the number of natural enemies (such as insects and birds) living on these pests, threatening the ecological balance A study in Scotland found that a aphid sucks the juice of Bt toxin from genetically engineered crops, and then it is preyed on by a beneficial insect, beetle Bt toxin protein is transferred to beetle and affects its reproduction A study from Canada reported that genetically engineered Bt crops can also poison another natural enemy of pests, membranous wing insects In the United States, section