After more than 30 years of progress and development, genetic engineering technology developed in the early 1970s has become the core content of biotechnology. Many scientists predict that biology will become the most important discipline in 2 1 century, and genetic engineering and related industries will become one of the leading industries in 2 1 century. The research and application of genetic engineering involves many fields such as agriculture, industry, medicine, energy and environmental protection.

Genetic engineering technology; Prospect; condition

First, the application of genetic engineering in plants.

Agriculture is one of the most widely used fields of transgenic technology. The purpose of crop biotechnology is to increase crop yield, improve quality and enhance crop resistance to adversity and pests. Genetic engineering has made remarkable achievements in these fields.

Due to the development of plant virus molecular biology, plant disease resistance genetic engineering has also been fully launched. Since it was found that tobacco mosaic virus coat protein gene was introduced into tobacco, the onset time in transgenic plants was obviously delayed or the symptoms were alleviated. The antiviral ability of plants was improved by introducing plant virus coat protein, and experiments have been carried out with many plant viruses. Great progress has also been made in enhancing plant resistance to bacterial and fungal diseases through genetic engineering. Plant resistance to adversity has always been a concern of plant biologists. Thanks to the cooperation of plant physiologists, geneticists and molecular biologists, new varieties (lines) of transgenic crops with waterlogging tolerance, salt tolerance, drought tolerance and cold tolerance have also been successful. The cold resistance of plants is particularly important for their growth and development. Scientists have found that there are some special protein in polar fish, which can inhibit the growth of ice crystals, thus avoiding freezing injury at low temperature and living normally in cold polar regions. Transgenic plants can be obtained by separating this antifreeze protein gene from fish genome and introducing it into plants. At present, this gene has been transferred to tomatoes and cucumbers.

With the improvement of living standards, people pay more and more attention to quality traits such as taste, mouthfeel, nutritional components and appreciation value. Practice has proved that genetic engineering can effectively improve the quality of plants, and more and more genetically engineered plants have entered the field of commercial production. In recent years, great progress has been made in improving crop quality by genetic engineering. For example, scientists from the International Plant Research Institute of the United States obtained the protein synthetic gene from soybean and successfully introduced it into potato to cultivate a high-protein potato variety with protein content close to soybean, which greatly improved its nutritional value and was widely welcomed by farmers and consumers. A lot of research has also been done on the improvement of color, flower fragrance and flower posture.

Second, the application of genetic engineering in medicine

At present, the genetic engineering application industry led by genetic engineering drugs has become one of the fastest growing industries in the world, and its development prospects are very broad. Genetic engineering drugs mainly include cytokines, antibodies, vaccines, hormones and oligonucleotides. They play an important role in preventing human tumors, cardiovascular diseases, genetic diseases, diabetes, and various infectious diseases including AIDS and rheumatoid diseases. In many fields, especially in difficult diseases, genetically engineered drugs have played a role that traditional chemical drugs cannot achieve. Interferon (IFN), which we are most familiar with, is a multifunctional cytokine developed by genetic engineering technology. Clinically, it has been used to treat leukemia, hepatitis B, hepatitis C, multiple sclerosis and rheumatoid arthritis.

At present, the AIDS vaccine developed by genetic engineering has completed the pilot test and entered the clinical verification stage; The "tumor gene missile" specially used to treat tumors will also be successfully developed in the near future. It can find and kill tumors purposefully, which will make it possible to cure cancer. Somatic gene biological injection specially developed by scientists from China, the United States and Germany and six research institutions at home and abroad for the treatment of hepatitis B, chronic hepatitis, chronic hepatitis C and liver cirrhosis finally solved the whole process from cutting and separation to swallowing hepatitis virus in hepatocytes, repairing and promoting hepatocyte regeneration. After four years of clinical trials, it is aimed at hepatitis patients all over the country. This gene research achievement is a revolutionary medical achievement in the field of international liver disease treatment after interferon and other drugs.

Thirdly, the application of genetic engineering in environmental protection

Environmental pollution caused by industrial development and other human factors has far exceeded the purification ability of microorganisms in nature, and has become a very concerned issue. Genetic engineering technology can improve the ability of microorganisms to purify the environment. The United States uses DNA recombination technology to connect four bacterial genes that degrade aromatic hydrocarbons, terpenoid hydrocarbons, polycyclic aromatic hydrocarbons and aliphatic hydrocarbons, and transfer them into a certain bacteria to construct a "superbacterium" that can degrade four organic substances at the same time. It can degrade two-thirds of hydrocarbons in the oil slick in a few hours, while natural strains need 1 year. Someone successfully expressed the Bt protein gene, bacillus sphaericus. It can kill mosquitoes and pests, but it is harmless to people and animals and does not pollute the environment. At present, genetically engineered bacteria have been developed, including bacteria for purifying pesticide DDT, bacteria for degrading dyes in water, engineering bacteria for degrading organochlorobenzene and chlorophenol in the environment, engineering bacteria for degrading TNT explosives in soil, genetically engineered bacteria and plants for adsorbing inorganic toxic compounds (lead, mercury, cadmium, etc.). ). DNA recombination technology, which came out in the late 1990s, can innovate genes, endow expression products with new functions and create brand-new microorganisms. For example, all genes of different bacteria that degrade a pollutant can be cloned by PCR technology, then treated and recombined in vitro by gene recombination technology, and finally introduced into a suitable vector, so that it is possible to produce one or several super strains with extraordinary degradation ability, thus greatly improving the degradation efficiency.

Four. prospect

Because genetic engineering uses DNA molecular recombination technology, many new gene combinations and new products with novel genetic traits can be created according to people's pre-design, which enhances people's subjective initiative and foresight in transforming animals and plants. But also played a revolutionary role in the diagnosis and treatment of human diseases, and made great contributions to population quality and environmental protection. Therefore, governments all over the world and some large companies attach great importance to the research, development and application of genetic engineering technology in order to seize this high-tech commanding height. Its application prospect is very broad. China's genetic engineering technology still lags behind developed countries, so we should speed up development and never miss the opportunity.

However, any science and technology is a "double-edged sword", which not only brings benefits to mankind, but also brings certain disasters to mankind. For example, gene drugs can not only cure hereditary diseases, malignant tumors, cardiovascular and cerebrovascular diseases, but also transform people's intelligence, physique, personality and appearance at will; Moreover, if cloning technology is not restricted and allowed to develop freely, it may eventually lead to the destruction of mankind. Also, although genetically modified animals and plants have not been found to be harmful to human beings, it does not mean that genetically modified animals and plants are safe. After all, these things are still new and need to be tested slowly in practice. Genetically modified organisms, like conventional breeding varieties, modify some of their characters or add new characters or eliminate the original unfavorable characters on the basis of the original varieties, but conventional breeding is through natural selection and inbreeding, the fittest survive and the unsuitable ones are eliminated. However, genetically modified organisms go far beyond the scope of kinship, and people still lack knowledge and experience about whether possible new combinations and new traits will affect human health and the environment. According to the current scientific level, it is impossible to predict it completely and accurately. Therefore, we should seize the opportunity, vigorously develop genetic engineering technology, and at the same time, we need strict management and pay full attention to the safety of genetically modified organisms.

refer to

Lou Shilin, Yang, Long Minnan, et al. Genetic Engineering [M]. Beijing Science Press 2002.

, Dong, Shi Bing. Research progress of insect-resistant genes in plants [J]. Forestry Science and Technology, 2002,27 (2): 22 26.

There is also an article/biology/Bess/exercise-collection/20065438+0a/gene/dd.htm.