One: In the production field, people can use genetic technology to produce genetically modified food. For example, scientists can implant genes that control the growth of meat in pigs into chickens, so that chickens can gain the ability to gain weight quickly. However, due to its high-tech content, fear of eating foreign genes in genetically modified food will change people's genetic traits, such as eating genetically modified pork will become active, drinking genetically modified milk will easily lead to galactose phobia and so on. Academician Zhang Qifa of Huazhong Agricultural University said: "Transgenic technology provides a new means for crop improvement, but it also brings potential risks. Gene technology itself can carry out accurate analysis and evaluation, thus effectively avoiding risks. The risk assessment of transgenic technology should refer to traditional technology. Scientific and standardized management can provide guarantee for the use of transgenic technology. Popular science and public education of basic knowledge of life sciences are very important. "
2. Military applications. Biological weapons have been used for a long time. Bacteria and poisonous gas make people pale. But now the legendary genetic weapon is even more terrible.
Third, we can also use genetic weapons in environmental protection. We can develop special gene drugs for some animals and plants that destroy the ecological balance, which can not only kill them efficiently, but also save costs. For example, if a genetic product can be killed in colleges and universities, it can save billions every year.
Science is a double-edged sword. Genetic engineering is no exception. We should give full play to the role of genetic engineering in benefiting mankind and curb its harm.
Fourth, medical care.
With the deepening of human research on genes, it is found that many diseases are caused by changes in gene structure and function. Scientists will not only discover defective genes, but also master how to diagnose, repair, treat and prevent them, which is the frontier of biotechnology development. This achievement will bring immeasurable benefits to human health and life. The so-called gene therapy refers to the use of genetic engineering technology to transfer normal genes into the cells of patients with diseases, to replace diseased genes, to express missing products, or to treat some genetic diseases by shutting down or reducing abnormally expressed genes. At present, more than 6,500 genetic diseases have been found, of which about 3,000 are caused by single gene defects. Therefore, genetic diseases are the main targets of gene therapy. 1990 carried out the first gene therapy in America. At that time, two 4-year-old and 9-year-old girls suffered from severe combined immunodeficiency due to lack of adenosine deaminase in their bodies. Scientists carried out gene therapy on them and achieved success. This pioneering work marks the transition of gene therapy from experimental research to clinical experiment. 199 1 year, the first clinical trial of hemophilia b gene therapy in China was also successful.
The latest development of gene therapy is that gene gun technology will be used in gene therapy soon. This method introduces specific DNA into muscle, liver, spleen, intestine and skin of mice through improved gene gun technology, and obtains successful expression. This success indicates that people may use gene gun to deliver drugs to specific parts of human body in the future, instead of traditional vaccination, and use gene gun technology to treat hereditary diseases.
At present, scientists are studying fetal gene therapy. If the current experimental efficacy is further confirmed, it is possible to extend fetal gene therapy to other genetic diseases, thus preventing the birth of newborns with genetic diseases and fundamentally improving the health level of future generations.
Verb (abbreviation of verb) Study on Genetic Engineering Drugs
Genetically engineered drugs are the expression products of recombinant DNA. Broadly speaking, anything that involves genetic engineering in the process of drug production can become a genetically engineered drug. The research in this field has a very attractive prospect.
The research and development of genetically engineered drugs has shifted from the molecular proteins of protein drugs such as insulin, human growth hormone and erythropoietin to protein drugs with smaller molecules. This is because protein's molecules are generally large and difficult to cross the cell membrane, thus affecting its pharmacological effects, and small molecule drugs have obvious advantages in this respect. On the other hand, the idea of treating diseases has been broadened, from simple drug treatment to the use of genetic engineering technology or genes themselves as treatment means.
Now, there is another problem that needs everyone's attention, that is, many infectious diseases that were conquered in the past have made a comeback because of bacterial resistance. One of the most noteworthy is tuberculosis. According to the World Health Organization, there has been a global tuberculosis crisis. Tuberculosis, which was about to be eliminated, has resurfaced, and a variety of drug-resistant tuberculosis has emerged. According to statistics, there are 65.438+72.2 million people infected with tuberculosis in the world, and 9 million people are newly infected with tuberculosis every year, and about 3 million people die of tuberculosis, which is equivalent to one person dying of tuberculosis every 654.38+00 seconds. Scientists also pointed out that there will be no cure for hundreds of people infected with bacterial diseases in the future, and at the same time, there are more and more viral diseases, which are hard to prevent. At the same time, however, scientists are also exploring ways to deal with it. They found some small antimicrobial peptides in human, insect and plant seeds. Their molecular weight is less than 4000, and there are only more than 30 amino acids. They have strong vitality to kill pathogenic microorganisms, such as bacteria, germs and fungi, and may become a new generation of "super antibiotics". In addition to using it to develop new antibiotics, this small peptide can also be used in agriculture to cultivate new varieties of disease-resistant crops.
Sixth, speed up the cultivation of new crop varieties
Scientists have made great progress in using genetic engineering technology to improve crops, and a new green revolution is coming. A remarkable feature of this new green revolution is that biotechnology, agriculture, food and medicine industries will merge together.
In 1950s and 1960s, due to the popularization of hybrid varieties, the increase of fertilizer use and the expansion of irrigation area, the crop yield doubled, which is known as the "green revolution". However, some researchers believe that it is difficult for these methods to further significantly increase crop yield.
The breakthrough of genetic technology enables scientists to improve crops in ways that traditional breeding experts can't imagine. For example, genetic technology can make crops release pesticides themselves, plant crops in dry land or saline-alkali land, or produce more nutritious food. Scientists are still developing crops that can produce vaccines and foods that can prevent diseases. Gene technology has also greatly shortened the time for developing new crop varieties. It takes seven or eight years to cultivate a new plant variety by traditional breeding methods. Genetic engineering technology enables researchers to inject any gene into plants and cultivate a brand-new crop variety, and the time is shortened by half.
Although the first genetically engineered crop varieties entered the market only five years ago, half of the corn, soybeans and cotton planted in the United States this year will use genetically engineered seeds. It is estimated that in the next five years, the market size of genetically modified agricultural products and food in the United States will expand from $4 billion this year to $20 billion, and reach $75 billion in 20 years. Some experts predict that "by the beginning of the next century, it is likely that every food in the United States will contain a little genetic engineering."
Although many people, especially consumers in European countries, have doubts about genetically modified agricultural products, experts point out that it is imperative to improve crops through genetic engineering. This is mainly due to the increasing pressure of the global population. Experts estimate that the global population will increase by half in the next 40 years, so the grain output needs to increase by 75%. In addition, the aging population brings more and more pressure to the medical system, so it is necessary to develop foods that can enhance human health.
Accelerating the cultivation of new crop varieties is also the common goal of developing biotechnology in developing countries in the third world. The research and application of agricultural biotechnology in China has been widely carried out and achieved remarkable benefits.
Seventh, molecular evolution engineering's research.
Molecular evolution engineering is the third generation of genetic engineering after protein Project. It simulates the evolution of organisms in nature by exerting selective pressure on the multi-molecular system dominated by nucleic acids in test tubes, thus achieving the purpose of creating new genes and new protein.
This requires three steps, namely amplification, mutation and selection. Amplification is to obtain a large number of copies of extracted genetic information DNA fragments; Mutation is to exert pressure on the gene level to mutate the bases on DNA fragments, providing raw materials for selection and evolution; Selection is to fix variation at the phenotypic level by survival of the fittest and elimination of the unsuitable. These three processes are closely linked and indispensable.
Now, using this method, scientists have obtained DNA molecules that can inhibit thrombin activity through directional evolution in test tubes. This DNA has anticoagulant effect, and may replace protein drugs for thrombolysis to treat myocardial infarction, cerebral thrombosis and other diseases.
Achievements of China's Gene Research
Scientific research aimed at deciphering all the genetic information of the human genome is one of the frontier topics that the international biomedical community has overcome at present. According to reports, the most concerned thing in this research is cloning, separating and identifying human disease-related genes and genes with important biological functions, so as to obtain the possibility of gene therapy for related diseases and the right to produce biological products.
The human genome project is an important part of the national "863" high-tech plan. In medicine, human genes are related to human diseases. Once the specific relationship between genes and diseases is clear, people can make gene drugs for diseases, which will have a great impact on human health and longevity. According to reports, the total number of human genetic samples is about 65,438+10,000, and about 8,000 have been discovered and sequenced.
In recent years, China has attached great importance to human genome research. With the support of the National Natural Science Foundation, the "863 Program" and local governments, national gene research centers with advanced scientific research conditions have been established in Beijing and Shanghai. At the same time, scientific and technological personnel keep up with the development of new technologies in the world and make breakthroughs in the key technologies of genetic engineering research and the industrialization of achievements. China's human genome research has been at the forefront of the world, and some genetically engineered drugs have begun to enter the application stage. At present, China's basic research in protein's gene mutation research, blood disease gene therapy, esophageal cancer research, molecular evolution theory, and leukemia-related gene structure research has reached the international leading level, and some have formed their own technical system. More than a dozen genetically engineered drugs, such as hepatitis B vaccine, recombinant interferon α, recombinant human erythropoietin, and transgenic animal drug manufacturers, have all entered the stage of industrialization.
Gene technology: dilemma and dual characteristics, it is not surprising that gene crops have caused public controversy. However, on both sides of the Atlantic belonging to the developed world, the treatment of transgenic technology is quite different, which is an intriguing phenomenon. When 40% of the farmland in the United States grows genetically modified crops, and most consumers buy genetically modified foods with equanimity, why do such foods encounter waves of shouts in Europe? From the direct social background, the current prevalence of "genetically modified phobia" in Europe is understandable. From 1986, mad cow disease was discovered in Britain, to this year's discovery of dioxin caused by contaminated chickens in Belgium, and the discovery of children's hemolysis caused by Coca-Cola in France. Europeans are quite nervous about food safety, and the hypothesis that genetically modified foods may harm human health is as daunting as conditioned reflex.
At the same time, Europe has always adopted a more sensitive and even radical attitude than the United States on environmental and ecological protection issues, which is another reason why genetically modified foods are in different situations in Europe and America. On the one hand, the media in European countries are more and more aware of environmental protection, and they often pursue or even exaggerate the problems that may endanger the environment and ecology, which greatly affects the public's attitude towards genetically modified issues. On the other hand, as a representative, the Green Party has risen in European politics in recent years, and its power in the government and parliament has been expanding, and its influence on the decision-making process is growing.
However, there seems to be a hidden but important deep-seated reason why Europeans adopt such an exclusive attitude towards transgenic technology. In fact, there are differences in values between Europe and the United States on the issue of genetic modification, which is also a dispute over economic interests. Different from general commodities, transgenic technology has a unique monopoly. Technically, American "life science" companies generally make their products have self-protection function through bioengineering. The most prominent is the "terminator gene", which can make seeds self-destruct and cannot be re-sown like traditional crop seeds. Another technology is that seeds must undergo some kind of "chemical catalysis" that only seed companies can master before they can develop and grow. Legally, genetically modified crop seeds are generally provided through a special lease system, and consumers are not allowed to keep and replant them themselves. The United States is the largest investor in costly genetic engineering research, and American companies engaged in the development of transgenic technology are familiar with the use of intellectual property rights and patent protection laws to seek huge returns. At present, the United States is considered to have controlled a considerable market share of genetically modified products, and thus can manipulate market prices. Therefore, resisting genetically modified technology is actually resisting the monopoly of the United States in this field.
Biotechnology is playing an increasingly important role in many fields: genetically modified products are everywhere in the agricultural field, and genetically modified crops have begun to occupy an important position in American agriculture; Biotechnology has made remarkable progress in the medical field. Some genetically engineered drugs have replaced conventional drugs, and the medical community has benefited from genetic research in several ways. The progress of cloning technology provides unprecedented opportunities for saving endangered species and exploring the treatment of many human diseases. At present, researchers are preparing to push biotechnology into more challenging fields. But recently, more and more people have begun to pay attention to the voice of vigilance against geneticists' behavior.
Today, people can study hundreds of gene matrices at the same time with the help of so-called DNA slicing. Gene research has reached such a high level of development. A few years later, with the end of the analysis of human genetic material, people began to focus on all means to systematically study the advantages and disadvantages of other parts of human genetic material. However, the development of biology also has its negative side: it can easily provide a new genetic basis for racism. People who are critical of new genetics always like to paint a terrible picture: endless experiments, manipulation and cloning, ruthless soldiers, factory workers with perfect genes ... genetic codes enable genetic researchers to go deep into people's hearts and provide them with tools to manipulate their lives. However, whether they can make genetics develop in a good direction is completely unpredictable.
Memorabilia of genetic engineering
From 1860 to 1870, Austrian scholar Mendel put forward the concept of genetic factor according to pea hybridization experiment and summarized Mendel's genetic law.
1909, Danish botanist and geneticist Johnson first put forward the word "gene" to express Mendel's concept of genetic factors.
1944, three American scientists isolated bacterial DNA (deoxyribonucleic acid) and found that DNA is a molecule carrying the genetic material of life.
1953, American Watson and Englishman Crick put forward the double helix model of DNA molecules through experiments.
1969 Scientists successfully isolated the first gene.
1990 10 The International Human Genome Project, known as the Apollo Moon Landing Program in life science, was launched.
From 65438 to 0998, a group of scientists founded Celera Gene Company in Rockwell, USA, to compete with the International Human Genome Project.
1998 12 the complete genome sequence of a small nematode has been determined, which is the first time that scientists have drawn the genome map of a multicellular animal.
1In September 1999, China was allowed to join the Human Genome Project and was responsible for determining 1% of the total sequence of the human genome. China is the sixth country to participate in the international human genome project after the United States, Britain, Japan, Germany and France, and it is also the only developing country to participate in this project.
1 99965438+February1day, the joint research team of the International Human Genome Project announced that the genetic code of the 22nd human chromosome has been completely decoded, which is the first time that humans have successfully completed the determination of the complete gene sequence of the human chromosome.
On April 6, 2000, Celera announced that it had cracked the complete genetic code of an experimenter, but it was questioned by many scientists.
At the end of April 2000, Chinese scientists completed the working framework of 1% human genome according to the deployment of the International Human Genome Project.
On May 8, 2000, German and Japanese scientists announced that the sequencing of chromosome 2 1 had been basically completed.
On June 26th, 2000, scientists published the working draft of human genome, which marked an important step for human beings to interpret their "book of life".
In June 5438+February 65438+April 2000, scientists in the United States and Britain announced that they had drawn a complete map of Arabidopsis genome, which was the first time that human beings had completely deciphered the gene sequence of a plant.
2001February 12 Chinese, American, Japanese, German, French and British scientists jointly published the human genome map and preliminary analysis results.
For the first time, scientists published the draft of "genetic information" of the human genome.
Gene research countries are competing for the global map of the gene age.
Let's take a look at the research on genetic science in countries around the world at the arrival of the new century.
Britain: As early as the mid-1980s, Britain had its first biotechnology enterprise, which was the earliest among European countries. Today, it has 560 biotechnology companies, and Britain accounts for half of the 70 listed biotechnology companies in Europe.
Germany: Recognizing that biotechnology will be the key to maintain Germany's future economic competitiveness, the German government passed legislation in 1993 to simplify the examination and approval procedures for biotechnology enterprises, and allocated1500,000 Deutsche Mark to set up three biotechnology research centers. In addition, the government also plans to spend 654.38+0.2 billion marks on the research of the human genome project in the next five years. 1999, German researchers applied for biotechnology patents, accounting for 14% in Europe.
France: In the past 10 years, the French government's funds for biotechnology have increased by 10 times. The most typical project is the so-called "Gene Valley" Science Park established by 1998 near Paris, where the most promising emerging biotechnology companies in France gather. Another 20 French cities are also planning to set up their own biotechnology parks in imitation of the "Gene Valley".
Spain: Mar Pharmaceutical Company is the representative of this country's biotechnology enterprises, specializing in finding anticancer substances from marine life. Among them, ET-743 is the most valuable one, which is a red anticancer drug extracted from the seabed ejecta in the Caribbean and Mediterranean. ET-743 is planned to be registered and produced in Europe in 2002, and will be used to treat common cancers such as bone cancer, skin cancer, ovarian cancer and breast cancer.
India: The Indian government funds more than 50 research centers across the country to collect human genome data. Due to the unique "caste system" and the intermarriage customs of some remote tribes, the gene bank of Indian population is the most complete in the world, and it is a very valuable database for scientists to find the pathology and treatment of genetic diseases. However, private biotechnology enterprises in India are still in their infancy.
Japan: The Japanese government plans to increase the funding for biotechnology research by 23% next year. A private company has also established the Dragon Gene Center, which will be the largest genome research institution in Asia.
Singapore: Singapore announced a $60 million genetic technology research project to study how diseases have different effects on Asians and whites. The plan focuses on analyzing genetic differences and what treatment methods are effective for Asians, so as to finally gain new knowledge of identifying and treating diseases; And set up high-tech companies to manufacture drugs and medical products derived from this research.
China: Participated in the Human Genome Project and determined the sequence of 1%, which brought a bright future to the bio-industry in China in the 2nd1century. This "1% project" has enabled China to enter the international advanced ranks of bio-industry, and also enabled China to naturally share all the achievements, resources and technologies of the Human Genome Project.