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PARIS
Four identical copies of Dolly, the famous cloned sheep died prematurely in 2003, already they served nine years and survive without problems revealed yesterday a study.
Debbie, Denise, Dianna and Daisy, identical sisters are “in good health”, according to researchers who study aging of cloned animals.
the quadruplets were created from the cells of the same mammary gland using a nuclear technique called transfer of somatic cell (SCNT).
Born 20 years ago on July 5, 1996, Dolly, the first mammal cloned, developed knee arthritis five years and died of lung disease at six, ie half the normal age for their race Finn-Dorset.
mishaps health of Dolly and his untimely death have highlighted the risks of cloning. Laboratory mice cloned also show a propensity for obesity and die young.
Kevin Sinclair, University of Nottingham, carefully examined the four “Dollies” born in July 2007 and nine others sheep cloned from different cell cultures.
the 13 children, aged between seven and nine, are the result of laboratory work to improve the efficiency of SCNT.
the researchers measured the tolerance of sheep glucose, their insulin sensitivity, blood pressure and bone health, in what they describe as the first comprehensive assessment of aging of cloned animals.
there were cases medium arthritis and severe, which are not unusual for his age. None of the sheep is lame as it was Dolly.
The SCNT involves removing the nucleus and its DNA into a cell other than an egg or sperm-a skin cell, for example and introduce an unfertilized egg that has been previously removed the nucleus.
once implanted, the egg reprograms the DNA and begins to develop an embryo. Knowledge that you have, no human being was ever created that way.
Despite recent improvements, the technique is still inefficient and expensive.
Just a handful of clones survived the birth.
“The consensus supported by the data collected is that those who survive are healthy and seem to age normally” says the study published in the journal Nature Communications .
Animal cloning is used in agriculture, especially to raise cattle, but also in the business of ” restore “people their dead pets
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