The recent branch in applied genetics is Genetic engineering or Biotechnology or Recombinant DNA technology. The genetic engineering permits cloning in animals breeding.
Clone is a population of cells or individuals which are genetically identical. With the death of an organism, a particular genotype is lost. Cloning is meant for preservation of the genotype of an organism. The cloning is of two types namely
i. Gene Cloning at molecular level
ii. Cloning of organisms.
Ian Wilmut of Rocline Institute, Edinburgh has produced a clone of adult lamb named Dolly in the year 1997. The genetic material from udder cells of one sheep was extracted and implanted into another sheep’s egg (that fails to embryonic development) after removing its genetic material. The fused cell developed into an embryo which was implanted into the uterus of another sheep which acted as surrogate mother. The young sheep born through surrogate mother is named as Dolly.
When a useful drug is prepared from a sheep the cloning of such sheep is nothing but establishment of drug factories. Wilmut has cloned Dolly for this purpose.
Dolly was cloned to produce Molly and Polly, two lambs cloned with a human gene for blood clotting factor IX. The milk of Molly and Polly contains Factor IX that can be extracted for use in treatment of human haemophilia.
Simian cloning (Cloning of monkeys) was carried out by Don Wolf (USA) in 1996 from an eight cell embryo. A Japan Scientist, The ruhikoVakayama has made cloning experiments in rats. He has produced number of embryos by using a nucleus and an ovum. A nucleus was extracted from rat’s tissue and injected into another cell without nucleus. Within six hours number of nuclei are produced from a single nucleus. He has created dozens of clones from them. He has also created clones to clones in addition to 50 similar rats of three generations.
Different opinions were expressed on human cloning. About 15 countries have signed an agreement on formulating laws to prevent human cloning. A professor of London university has expressed that cloning of body organs and cells is medically beneficial than cloning of entire body.
Indian council of Medical Research (ICMR) has also called upon to ban human cloning in India. ICMR has suggested that cloning experiments can be made by embryo splitting but not by nuclear transplantation.
Biotechnology proves that wonderful results can be obtained by careful gene cloning. One can look forward to yield better results instead of bad consequences by this process called cloning.