The Human Brain Cloning Robots Nanotechnology Gene Selection
	Cloning How do you make a clone? A clone is a copy. To make one you need two cells: a donor cell from the animal you want to clone and a living egg cell from another animal. Scientists remove the egg cell's nucleus and insert a donor's nucleus into the egg cell. Then, they add a spark of electricity to help fuse the egg and donor material. Finally, they either implant the egg cell into a surrogate mother right away, or grow it in the lab for several cell divisions, then implant it. The future of cloning Cloning is a form of asexual reproduction-that is, there is no meeting of sperm and egg. Some think humans may reproduce in the future without sex. However, many scientists think we will not be cloning humans in the future. They believe that we will use cloning to make animals that carry human genes. These genetically altered animals would produce human proteins or organs that could be used to help humans. Cloning Take a look at clones from the past and take a peek at what may be possible in the future. 1952 Tadpoles Northern leopard frogs were the first animals cloned by the nuclear transfer method (transferring the nucleus of an embryonic cell into an egg cell). 1984 Sheep A sheep was the first mammal cloned using the nuclear transfer method (transferring the nucleus of an embryonic cell into an egg cell). 1996 Dolly, the sheep Dolly was the first animal ever cloned from adult cells instead of embryonic cells. 1997 Polly, the lamb Polly was the first clone genetically altered to contain a human gene. 1998 Mouse Mouse embryos start developing differently than other mammals and were not successfully cloned until the late 1990s. Mice are important because they are often used as models for many human diseases. 2000 Tetra, the rhesus monkey Tetra was the first primate cloned from a divided embryonic cell. An eight-celled embryo was divided into four equal parts and Tetra developed from one of those parts. 2000 Mouflon sheep This was the first cloning of an endangered species and the first time scientists used genetic material from recently dead animals.
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