Dolly was a female domestic sheep, the first cloned mammal from an adult somatic cell, using the process of nuclear transfer. She was cloned by LAN Wilmut, Keith Campbel and colleagues at the Roslin Institute near Edinburgh in Scotland. She was born on 5 July, 1996 and she lived until the age of six.
( 14 February, 2004 )
The cell used as the donor for cloning of Dolly was taken from a mammary gland, and the production of a healthy clone therefor proved that a cell taken from a specific part of the body could recreate a whole individual. As Dolly was cloned from part of mammary gland, she was named after the famously curvaceous country western singer Dolly Parton.
Birth
The technique of somatic cell nuclear transfer, was used where the cell nucleus from an adult cell was transferred into an unfertilized oocyte (beveloping egg cell). The nucleous of the oocyte was removed.The hybrid cell was then stimulated to divide by an electric shock, and when it develops into a blast cyst it was implanted in a foster mother.
Dolly was the first clone produced from a cell taken from an adult mammal. The production of Dolly showed that genes in the nucleus of such a mature differentiated somatic cell are still capable of reverting back to an undifferentiated totipotent state, creating a cell can then go on to develop into any part of animal. However, this reprogramming process is not perfect and embryos produced by nuclear transfer often show abnormal development.
As a consequence of these difficulties in development, cloning mammals by nuclear transfer isstill highly inefficient, with Dolly the only lamb that survived to adulthood from 277 attempts. However, he birth is still recognized as one of the major stepping stones in the development of modern biology. Wilmut, who led the team that created Dolly, announced in 2007 that the nuclear transfer technique may never be sufficiently efficient for use in humans.
Life
Dolly lived for her entire life at Roslin Institute. There she was bred with a Welson Mountain ram and produced six lambs in total. Her first lamb called Bonnie, was born in April 1998. the next year Dolly produced twin lambs Saily and Rosie, and she gave birth to triplets Lucky, Darcy and Cotton in the year after that. In the autumn of 2001, atthe age of five, Dolly developed arthritis and began to walk stiffly, but this was successfully treated with anti-inflammatory drugs.
Death
On 14 February 2003, Dolly died because of a progressive lung disease and severe arthritis. A Finn Dorset such as Dolly has a life expectancy of around 11 to 12 years, but Dolly lived to be only six years of age. A post-Morten examination showed she had a from of lung cancer called Jaagsiekte, which is a fairly common disease of sheep and is caused by the retrovirus JSRV. Roselin scientists stated that they did not think there was a connection with Dolly's being a clone, and that other sheep in the same flock had died of the same disease. Such lung diseases are a particular danger for sheep kept indoors, and Dolly had to sleep inside for security reasons. Some have speculated that a contributing factor to Dolly's death was that she could have been born with a genetic age of six years, the same age as the sheep from which she was cloned. One basis for this idea it was found that Dolly's cells were shot, which typically is a result of the ageing process. The rosin Institute has stated that intensive health screening did not reveal any abnormalities in Dolly that could have come from advanced aging.
Legacy
After cloning was successfully demonstrated through the production of Dolly, many many other large mammals have been cloned, including horses and bulls. The attempt to clone argali sheep did not produce viable embryos.The attempt to clone a bull was more successful, as were the attempt to clone mouflon (a from of wild sheep), both resulting in viable offspring. In 2005 a dog, snappy, was cloned by Korean stem cell researcher, Hwang Woo-Suk. Although cloning may eventually become a viable tool for preserving endangered species and important in the future production of transgenic livestock, animal conservation professionals point out that cloning does not alleviate the problems of loss of genetic diversity and habitat, and so must be considered an experimental technology for the time.
Other Species cloned
The modern cloning techniques involving nuclear transfer have been successfully performed on several species. Landmark work in cloning is listed below:
>Carp: (1963) Chinese, embryologist Tong Dizhou produced the world's first cloned fish by inserting the DNA from a cell of a male carp into an egg from a female carp.
>Mice (1986) A mouse "Masha" was the first successfully cloned mammal by Soviet scientists Chaylakhyan, Veprencev, Sviridova, and Nikitin.
>Sheep: (1996) Steen Willadsen. Megan and Mo-rag from early differentiated embryonic cells.
>Dolly the Sheep from a somatic cell in 1997.
>Rhesus Monkey: Tetra (January 2000) from embryo splitting.
>Gaur: (2001) was the first endangered species cloned.
>Cattle: Alpha and Beta (males, 2001) and (2005) in Brazil.
>Cat: Copy Cat "CC" (female, late 2001), Little Nicky, 2004, was the first cat cloned for commercial reasons.
>Mule: Idaho Gem, a john mule was born on 4 May 2003, the first horse-family clone.
>Horse: Prometea, (28 May 2003). Haflinger female the first cloned horse was born.
>Water Buffalo: (February 6, 2009), Samrupa was the first cloned water buffalo. It was born in India's Karna l
National Diary Research Institute but died five days later due to lung infection.
>Camel: (2009) Injaz, the first cloned came.
( 14 February, 2004 )
The cell used as the donor for cloning of Dolly was taken from a mammary gland, and the production of a healthy clone therefor proved that a cell taken from a specific part of the body could recreate a whole individual. As Dolly was cloned from part of mammary gland, she was named after the famously curvaceous country western singer Dolly Parton.
Birth
The technique of somatic cell nuclear transfer, was used where the cell nucleus from an adult cell was transferred into an unfertilized oocyte (beveloping egg cell). The nucleous of the oocyte was removed.The hybrid cell was then stimulated to divide by an electric shock, and when it develops into a blast cyst it was implanted in a foster mother.
Dolly was the first clone produced from a cell taken from an adult mammal. The production of Dolly showed that genes in the nucleus of such a mature differentiated somatic cell are still capable of reverting back to an undifferentiated totipotent state, creating a cell can then go on to develop into any part of animal. However, this reprogramming process is not perfect and embryos produced by nuclear transfer often show abnormal development.
As a consequence of these difficulties in development, cloning mammals by nuclear transfer isstill highly inefficient, with Dolly the only lamb that survived to adulthood from 277 attempts. However, he birth is still recognized as one of the major stepping stones in the development of modern biology. Wilmut, who led the team that created Dolly, announced in 2007 that the nuclear transfer technique may never be sufficiently efficient for use in humans.
Life
Dolly lived for her entire life at Roslin Institute. There she was bred with a Welson Mountain ram and produced six lambs in total. Her first lamb called Bonnie, was born in April 1998. the next year Dolly produced twin lambs Saily and Rosie, and she gave birth to triplets Lucky, Darcy and Cotton in the year after that. In the autumn of 2001, atthe age of five, Dolly developed arthritis and began to walk stiffly, but this was successfully treated with anti-inflammatory drugs.
Death
On 14 February 2003, Dolly died because of a progressive lung disease and severe arthritis. A Finn Dorset such as Dolly has a life expectancy of around 11 to 12 years, but Dolly lived to be only six years of age. A post-Morten examination showed she had a from of lung cancer called Jaagsiekte, which is a fairly common disease of sheep and is caused by the retrovirus JSRV. Roselin scientists stated that they did not think there was a connection with Dolly's being a clone, and that other sheep in the same flock had died of the same disease. Such lung diseases are a particular danger for sheep kept indoors, and Dolly had to sleep inside for security reasons. Some have speculated that a contributing factor to Dolly's death was that she could have been born with a genetic age of six years, the same age as the sheep from which she was cloned. One basis for this idea it was found that Dolly's cells were shot, which typically is a result of the ageing process. The rosin Institute has stated that intensive health screening did not reveal any abnormalities in Dolly that could have come from advanced aging.
Legacy
After cloning was successfully demonstrated through the production of Dolly, many many other large mammals have been cloned, including horses and bulls. The attempt to clone argali sheep did not produce viable embryos.The attempt to clone a bull was more successful, as were the attempt to clone mouflon (a from of wild sheep), both resulting in viable offspring. In 2005 a dog, snappy, was cloned by Korean stem cell researcher, Hwang Woo-Suk. Although cloning may eventually become a viable tool for preserving endangered species and important in the future production of transgenic livestock, animal conservation professionals point out that cloning does not alleviate the problems of loss of genetic diversity and habitat, and so must be considered an experimental technology for the time.
Other Species cloned
The modern cloning techniques involving nuclear transfer have been successfully performed on several species. Landmark work in cloning is listed below:
>Carp: (1963) Chinese, embryologist Tong Dizhou produced the world's first cloned fish by inserting the DNA from a cell of a male carp into an egg from a female carp.
>Mice (1986) A mouse "Masha" was the first successfully cloned mammal by Soviet scientists Chaylakhyan, Veprencev, Sviridova, and Nikitin.
>Sheep: (1996) Steen Willadsen. Megan and Mo-rag from early differentiated embryonic cells.
>Dolly the Sheep from a somatic cell in 1997.
>Rhesus Monkey: Tetra (January 2000) from embryo splitting.
>Gaur: (2001) was the first endangered species cloned.
>Cattle: Alpha and Beta (males, 2001) and (2005) in Brazil.
>Cat: Copy Cat "CC" (female, late 2001), Little Nicky, 2004, was the first cat cloned for commercial reasons.
>Mule: Idaho Gem, a john mule was born on 4 May 2003, the first horse-family clone.
>Horse: Prometea, (28 May 2003). Haflinger female the first cloned horse was born.
>Water Buffalo: (February 6, 2009), Samrupa was the first cloned water buffalo. It was born in India's Karna l
National Diary Research Institute but died five days later due to lung infection.
>Camel: (2009) Injaz, the first cloned came.
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