REPRODUCTIVE CLONING PROCESS
Early methods of cloning in the 1970s involved a technology called embryo splitting, or the separation process. Embryos were split into several cells and then implanted into a surrogate mother for growth and development. But there’s a limited number of splits that could be made, and only a few clones could be produced from one egg. The characteristics of the clone were also unpredictable because scientists were cloning from an embryo whose traits could not be predicted.
Unlike the embryo splitting method, some scientist used the somatic cell nuclear transfer in other words (SCNT). Somatic cells are any cells of the body except sperm & eggs from the animal to be cloned. This method can be used to make an unlimited number of copies of one animal. Many animals were cloned after this discovery such as cattle, mice, goats, pigs, rabbits, & even cats. This method has been around since 1996 when cloning first took place with the birth of Dolly the sheep, the world's first mammal cloned from an adult cell. In the SCNT process starts with an oocyte or unfertilized egg. Scientists remove the oocyte's nucleus, which contains the egg's genes. After removing it all that remains of the nucleus is a cell that contains nutrients essential for embryo development and other cellular machinery. The cell's nucleus is cultured in an incubator and then injected under the coating of the unfertilized oocyte. Then stimulated by a mild electrical pulse, the oocyte cytoplasm and the genetic material from the donated somatic cell combine. If the fusion is successful, the resulting fused cell divides just as if it were a fertilized egg and produces an embryo. The embryo is placed in the uterus of a surrogate mother. If the development proceeds normally, an animal clone will be born.
