Dolly,
the famous cloned sheep represents the Holy Grail of human reproduction.
Why? Because for the first time it was shown that scientists could
overcome the problem of cell differentiation. Most cells in the human
body differentiate into specific kinds of cells. Once they differentiate
they can only make that kind of cell. For example, blood cells make
more blood cells and skin cells make more skin cells.
Dolly was made from a mammary (breast) cell and showed that not only could a mammary cell make more mammary cells, but that it could make an entire lamb. (This is not actually a picture of Dolly, just a lamb. You may copy and use this picture as you like.)
Dolly proves in theory that scientists can take any kind of cell from a human body that contains DNA and make a baby. The baby would be a clone (identical twin) of the adult from which the cell came.
Since they used a mammary cell's DNA why
didn't the scientists just get a bunch of mammary cells to grow instead
of a baby? When the DNA was taken out of the mammary cell and placed
in an egg cell (ovum) from another sheep, apparently whatever is inside
the egg cell caused the DNA to lose its differentiation and return to the
germ cell state, capable of becoming anything, not just mammary tissue.
February 16, 1998 US Scientists cloned a Holstein cow
Using DNA from the
cell of a 30 day old fetus, scientists in the United States were able to
clone a calf.
They named the Holstein
calf, Gene.
July 5, 1998. A cow was cloned into two calves in Japan
Using cells from an adult cow, Japanese scientists cloned the cow into two calves born Sunday, July 5, 1998.
Toyokazu Morita, an official of the Ishikawa Prefectural Livestock Research Center, was involved in announcing the cloning.
The Kinki University
animal husbandry research group was also involved in the project.
July 22, 1998Mice are cloned
Mice have been cloned. It was announced
in the press that Dr Yanagimachi from the University of Hawaii and colleagues
had successfully cloned mice. The scientific article is to appear
in the journal Nature.
A Journal for Cloning is Planned
A new scientific journal to be called Cloning:
Science and Policy, has been launched. The journal is going to be
co-edited by Ian Wilmut, Ph.D., and Lee Silver, Ph.D. The Journal
is going to be published by Mary Ann Liebert, Inc., publishers (www.liebertpub.com).
The first issue is expected in December, 1998.
August 19, 1998 Scientists announce that a near-extinct species has been cloned
David Wells, led
the effort at the Ruakura Research Center in Hamilton, New Zealand to clone
the last cow a species that once inhabited Enderby Island in the Aukland
Islands.
The dog, Missy, is to be cloned
The Associated Press announced 8/25/98 that a
wealthy couple donated $2.3 million to Texas A & M University to clone their
dog. Dr. Mark Westhusin, co-director of the Reproductive Sciences Laboratory,
is one of the scientists involved in the project. Lou Hawthorne, president
of Bio Arts and Research Corporation (BARC), a San Francisco corporation, helped
negotiate the deal. The donors wish to remain anonymous.
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