I to enumerate pros and cons,let everybody comment?Leon:1) cloning technology can relieve those who cannot become the mother of women suffering.2) cloning experiments to promote the implementation of the genetics of development,for "create" can the animal organs transplanted opened up a prospect.3) cloning technology also can be used to test fetal genetic defects.Will be fertilized,used to detect various genetic disease cloned embryos and uterus,cloning and genetic characteristics of fetus develops in exactly the same.4) cloning technology used for treatment of the nervous system damage.Adult nervous tissue regeneration,but no stem cells can repair neurological damage.5) to in vitro fertilization surgery,doctors often need to connect multiple fertilized implanted in the womb,with a into pregnancy stages from screening.But many women can only provide an egg for fertilisation.Through cloning can well solve the problem.The eggs can clone into multiple for fertilization,which greatly improve pregnancy rate.Disadvantages:1) cloning would reduce the genetic variation,through cloning produces the individual has the same genetic,the same diseases sensitivity,a disease could destroy the generated by cloning of groups.Can imagine,if one country herds will have the same cloning product,a less severe virus could destroy the national husbandry.2) cloning technology use will make people tend to multiply the existing population of the most value of the individual,rather than by natural laws to promote the whole population of the muck.In this sense,the cloning technology to interfere with the natural evolution process.3) cloning technology is an expensive technology,need a lot of money and biological professional participation,failure rate is very high.Dolly is 277 experiments only results.Although now developed more advanced technology,the success rate was only to reach 2-3%.4) transgenic animals raised the risk of infection.For example,if a drug milk cow production infected with virus,which may be through milk infection patients 5) cloning technology applied to the human body will lead to the offspring of artificial control genetic traits.Cloning technology debate whether to allow the core is the development of early human embryos for genetic operation.This is many ethicists not acceptable.6) cloning technology can also be used to create "superman," or have strong physique but mental retardation.Moreover,if cloning technology can effectively use among humans,men also lost genetic significance.7) cloning technology to the effects of family relationships will also is huge.A father's DNA cloning generated children can as father's twin brother,only delayed decades was born just.It is hard to imagine that,when a person find yourself is simply another person's completely reproductions,he (or she) what it feels like to be?Say so,science and technology is sometimes a double-edged sword,advantages and disadvantages,and don't have no standard answer!Just watching people such use!