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When Will
Cat Cloning Become Available?
Many of the individual techniques already
exist. The technology for storing tissue has long
been available. It similar to that which is used
for storing sperm, eggs or embryos for human
fertility treatment. Stored sperm has long been
used for artificial insemination of cattle so that
the farmer doesn't have to keep a bull (most bulls
are aggressive and difficult to handle). Skin can
be grown in the laboratory allowing a patient's
own skin to be grafted onto him.
Scientists have already split fertilized eggs
into individual cells to give rise to multiple fetuses.
They have merged pairs of fertilized eggs into a
single egg to give rise to a "mosaic"
offspring (one which looks perfectly normal but
which a mixture of genetically different cells in
its body). Most of these things have been done
with mice, however scientists have merged the
embryos of a sheep and a goat to create a hybrid
called a "geep". Cloning a new
individual from a cell other than an egg cell has
always been a challenge. For many years it was
possible to clone simpler animals e.g. frogs, but
not more complex ones.
Cloning hit global headlines in 1997 after
Scottish scientists at the Britain's Roslin
Institute, UK, successfully cloned Dolly from an
adult sheep cell. Since then, researchers have
replicated mice and other creatures including an
endangered Gaur (a cow bore the Gaur calf; the
calf died of dysentery but this was not related to
the fact that it was a clone). Sheep, goats, cows
and pigs have been cloned. In the most efficient
and successful cloning experiment to date, dozens
of mice over six generations were cloned from a
single mouse.
This has led to several avenues of
research such as the cloning of a mammoth from
tissue frozen in Siberia or the cloning of
dinosaurs (such as depicted in "Jurassic
Park"). There is hope for resurrecting
recently extinct species such as the quagga (a
type of zebra), thylacine (Tasmanian wolf) or dodo
using DNA from taxidermized or preserved
specimens. "As dead as a dodo" might no
longer be true.
Right now, mammoths and dinosaurs are a long
way into the future as well as being a long way in
the past. However, scientists at commercial
cloning companies are feverishly manipulating
genes in hopes of becoming the first to clone a
domestic cat. But to do this, there are major
problem areas to be overcome.
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