In humans also clones are seen in the form of twins, but they are not identical to their parents. Dolly, the sheep was the first clone to be produced with the adult cell, rather than the embryo. After this, laboratories around the world, have witnessed the cloning of mice, frogs, and even cows.
The science of cloning is directed towards the generation of a genetically identical 'copy' of a plant or animal. In the case of plants, every cutting taken to generate another plant is essentially cloning.
The hype created around the cloning of Dolly came from the fact that she was the first mammal ever, to be cloned from an adult cell. However, this major achievement also attracted a lot of ethical concern among researchers, the world over. Animal cloning is a very complex and difficult procedure, with a very low success rate.
In Dolly, the nucleus of an udder cell was used. The nucleus was reprogrammed by altering the 'culture' medium, in which the cells were kept alive. This nucleus was then injected into an unfertilized egg cell which didn't have nucleus. This was done with the help of short electrical pulses, which caused the udder cell nucleus and enucleated egg cell to fuse.
The chance of the correct fusion is literally at a ratio of 1:300! The main motive behind the initial experiment with Dolly, at the Roslin Research Center, was to identify and commercialize medicines in the milk of animals. These medicines are believed to help cure hemophilia, cystic fibrosis, and certain lung conditions.
With the success in animal cloning, the scientists are now looking into generating human antibodies to fight infectious diseases and even cancer. Once successful, this technique can be applied to breed 'form flocks' of clones that are genetically engineered and complete with medicines in their milk.
A combination of various genetic techniques and cloning is making the supply of suitable donor organs a distinct possibility. The study of animal cloning gives man a better understanding of the process of development of the embryo.
It also enables the understanding of what is termed as 'aging' and the various age-related diseases. Scientists the world over are considering cloning as a medium to create better models of diseases to progress in finding effective treatments for those diseases.
Scientists are now looking into ways to improve this technology. Scientists are also working on better culture mediums for the procedure. However, there is still a lot of apprehension about the technical difficulties involved in cloning human cells. The possible rise in egg donations, surrogate pregnancies, and rate of miscarriage is of prime concern.
Human cloning has been banned by the Council of Europe. In America also, reproductive cloning is banned since the first time came in the California legislature in the year 1997. However, therapeutic cloning, where the cell nucleus is replaced to treat certain disease, is a boon in tissue engineering.
Therapeutic cloning in humans can be a revolution in cell and tissue transplantation for the treatment of diseases. Animal cloning for research or medical purposes must be first approved within the set paradigms of the Animals Scientific Procedures Act of 1986.
The act is designed to address animal welfare alongside important medical research. Animal cloning is great research material and base, but the law governing the activity and the applicable bans in certain cases are there for a purpose and must be adhered to. It is essential for us not to tip the balance of life in our pursuit of excellence.