Nuclear transferency - Dolly Sheep

Nuclear transferency - Dolly Sheep

Dolly the sheep May have been the world 's most famous clone, but she was not the first. Cloning Creates a genetically identical copy of an Animal or plant. Many animals - Including frogs and cows - Dolly had been cloned before. Often Plants are cloned - taking a cutting produces a clone of the original plant. Also Human identical twins are clones.

How Dolly was cloned

To produce Dolly, the scientists used the nucleus of an udder cell from a six-year-old Finn Dorset white sheep. The nucleus contains nearly all the cell's genes. They had to find a way to 'reprogram' the udder cells - to keep them alive but stop them growing - which They Achieved by altering the growth medium (the 'soup' in Which the cells were kept alive). Then They injected the cell into an unfertilised egg cell Which had had its nucleus removed, and made ​​the cells fuse by using electrical pulses. The unfertilised egg cell came from a Scottish Blackface ewe. When the research team had managed to fuse the nucleus from the adult cell with the white sheep egg cell from the black-faced sheep, They needed to make sure the Resulting cell That would Develop into an embryo. They cultured it for six or seven days to see if it divided and developed normally, before implanting it into a surrogate mother, another Scottish Blackface ewe. Dolly had a white face.

What happened to Dolly?

Born on 5 July 1996, she was euthanased on 14 February 2003, aged six and a half. Sheep can live to age 11 or 12, but Dolly Suffered from arthritis in a hind leg joint and from sheep pulmonary adenomatosis, to virus-induced lung Tumour to Which prone sheep are raised indoors.