Cloning is the process of generating a genetically identical copy of a cell or an organism. Cloning happens often in nature—for example, when a cell replicates itself asexually without any genetic alteration or recombination. Prokaryotic organisms (organisms lacking a cell nucleus) such as bacteria create genetically identical duplicates of themselves using binary fission or budding. In eukaryotic organisms (organisms possessing a cell nucleus) such as humans, all the cells that undergo mitosis, such as skin cells and cells lining the gastrointestinal tract, are clones; the only exceptions are gametes (eggs and sperm), which undergo meiosis and genetic recombination.
One of the main drawbacks of cloning is that if the original organism has genetic defects, these transfer to the clone as a copy of the original. The first clone, Dolly the sheep, born to a surrogate in 1996, was a genetic copy of a six-year old sheep. Dolly only lived to six years old herself, the bottom end of a sheep’s average life expectancy. At the age of five she developed arthritis, and the researchers put her to sleep at age six because of tumors in her lungs, which may have been in the genome of the original.
The moral and ethical arguments of cloning mostly refer to human cloning and human reproductive cloning. One of the problems of creating a cloned copy of a human being is that it creates a moral and ethical dilemma. Since the original and the copy are both human beings, but separate, like identical twins (nature’s version of cloning), this means that the clone has the same rights as the original and it would be illegal to use the clone’s parts or organs for replacement in the original. Some researchers argue that the cloning a child using the genetic material of the donor imposes an unfair situation upon the clone, as the clone has lost the right to have its own genetic material because the original forced its genes onto the clone.