Today's cloning refers to the asexual reproduction of organisms through somatic cells and the population of offspring individuals with exactly the same genotype formed through asexual reproduction. Cloning can also be understood as copying, copying, that is, producing the same copy from the prototype, and its appearance and genetic genes are exactly the same as the prototype.
1February, 1997, the news that Dolly the Sheep was born immediately attracted the attention of the whole world. This cloned sheep bred by British biologists through cloning technology means that human beings can use a somatic cell in an animal to create the same life as this animal, breaking the eternal laws of nature.
Pro: Cloning technology can relieve the pain of women who can't be mothers.
The implementation of cloning experiment has promoted the development of genetics and opened up a prospect for "manufacturing" animal organs that can be transplanted into human body.
Cloning technology can also be used to detect fetal genetic defects. Cloned fertilized eggs are used to detect various genetic diseases, and cloned embryos have exactly the same genetic characteristics as fetuses developed in uterus.
Cloning technology can be used to treat the injury of nervous system. Adult nerve tissue has no ability to regenerate, but stem cells can repair nervous system damage.
In vitro fertilization, doctors often need to implant multiple fertilized eggs into the uterus in order to choose one of them to enter the pregnancy stage. But many women can only provide one egg for fertilization. This problem can be well solved by cloning. This egg cell can be cloned into multiple cells for fertilization, thus greatly improving the success rate of pregnancy.
Disadvantages: Cloning will reduce genetic variation. Individuals produced by cloning have the same genetic genes and the same disease sensitivity, and a disease can destroy the entire population produced by cloning. It is conceivable that if all cattle in a country are the same cloned product, a slight virus may destroy the animal husbandry of the whole country.
The use of cloning technology will make people tend to breed the most valuable individuals in the existing population, rather than promoting the survival of the fittest in the whole population according to the laws of nature. In this sense, cloning technology interferes with the natural evolution process.
Cloning technology is an expensive technology, which requires a lot of money and the participation of biological professionals, and the failure rate is high. Dolly is the only result of 277 experiments. Although more advanced technology has been developed, the success rate can only reach 2-3%.
Transgenic animals increase the risk of disease transmission. For example, if a cow producing medicinal milk is infected with a virus, the virus may infect patients through milk.
The application of cloning technology to human body will lead to the artificial control of genetic traits of offspring. The core of the controversy caused by cloning technology is whether genetic manipulation of human embryos can be allowed in early development. This is unacceptable to many ethicists.
Cloning technology can also be used to create "Superman", or people who are physically strong but mentally retarded. Moreover, if cloning technology can be effectively used in humans, men will lose their genetic significance.
The impact of cloning technology on family relations will also be enormous. A child born from his father's DNA clone can be regarded as his father's twin brother, but the birth time has been delayed for decades. It's hard to imagine how a person will feel when he finds himself just a copy of another person.