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What is cloning? Cloning is the creating of a genetically copy of an individual.
What are the risks of cloning? Many clones have abnormalities that cause them to die during
pregnancy or soon after being born, etc.
Human cloning is at the heart of the cloning debate. It is probably the one area of cloning
that people have the most concern about. When asked about human cloning many people
think of Frankstein's monster or have vision of people emerging from vats where they have
been grown-all the stuff of science-fiction books and films.
How far have the scientists come along along to this vision of the future?
The first step on the road to human cloning started with the first test-tube baby in 1978.
This made use of a revolutionary technique in which a human egg was fertilized outside the
body. Today this technique, called in vitro fertilization (IVF), is carried out routinely on
infertile women. Infertility is often caused by blocked fallopian tubes, which lead from the
woman's ovaries (where her eggs are stored). Fertilization normally takes place in one of the
fallopian tubes.IVF treatment involves removing some of woman's eggs from her ovaries
and fertilizing them externally. The resulting embryo is returned to her uterus pregnancy can
proceed as normal.
The first stage in IVF treatment is hormone treatment to get the woman's ovaries to
produce many eggs. The eggs are collected by inserting a hollow needle through the wall of
the vagina (the passage way leading to the uterus). The eggs are placed in a fluid that is
similar to the one that exists in the fallopian tubes. Healthy sperm are added to the fluid and
fertilization takes place. The fertilized egg cells are grown until they reach the four-to eight-
cell embryo stage. The embryos are examined to make sure they are healthy and then two
or three are implanted in the uterus. By implanting more than on there is a greater chance of
success. Occasionally, all three survive and the woman gives birth to triplets. Any unused
embryos can be stored in liquid nitrogen in case the first attempt is unsuccessful.
Sometimes, women may give permission for any spare embryos to be used for research.
IVF treatment is very painful for the women and is not without risk. It would be safer and
cheaper for the laboratory to take one egg. Fertilize, and then split it to create many
embryos. These embryos would develop into individuals who were identical to each other
but different from their parents. Any woman who could not producing eggs could see eggs
from a donor. The nucleus would be removed from the donor egg and replaced with DNA
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This way the child would be a clone of one of its
There are some procedures that could help women who miscarry. One of the causes of a
miscarriage is faulty cytoplasm in the cells of the embryo. This could be overcome by using a
cloning technique. First, a fertilized egg cell would be produced using IVF. The nucleus of this
cell would be removed and placed inside an empty donor egg with a healthy cytoplasm.…read more