Dolly (sheep) facts for kids
Dolly (taxidermy)
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| Other name(s) | 6LLS (code name) |
|---|---|
| Species | Domestic sheep (Finn-Dorset) |
| Sex | Female |
| Born | 5 July 1996 Roslin Institute, Midlothian, Scotland |
| Died | 14 February 2003 (aged 6) Roslin Institute, Midlothian, Scotland |
| Resting place | National Museum of Scotland (remains on display) |
| Nation from | United Kingdom (Scotland) |
| Known for | First mammal cloned from an adult somatic cell |
| Offspring | 6 lambs (Bonnie; twins Sally and Rosie; triplets Lucy, Darcy and Cotton) |
| Named after | Dolly Parton |
Dolly (born July 5, 1996 – died February 14, 2003) was a female sheep. She was the first mammal ever cloned from an adult body cell. This was a big step in science!
Scientists at the Roslin Institute in Scotland created Dolly. They used a special method called nuclear transfer. This method took a cell from a sheep's udder. Dolly's birth showed that a full animal could be made from a mature cell. This cell came from a specific part of the body. Many people think Dolly was the first animal cloned. But she was actually the first cloned from an adult cell. Other animals had been cloned before her.
Dolly lived her whole life at the Roslin Institute. She even had several lambs of her own. She was put to sleep when she was six years old. This was because she had a serious lung disease. Scientists said this disease was not linked to her being a clone. After she died, Dolly's body was preserved. You can see her on display at the National Museum of Scotland.
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How Dolly Was Made
Dolly was cloned by a team of scientists. These included Keith Campbell and Ian Wilmut. They worked at the Roslin Institute in Scotland. This institute is part of the University of Edinburgh. A company called PPL Therapeutics also helped.
Dolly was born on July 5, 1996. She passed away on February 14, 2003. She had a lung disease. This disease was common in sheep. Scientists did not believe it was linked to her being a clone. Dolly has been called "the world's most famous sheep."
The cell used to create Dolly came from a sheep's udder. An udder is a mammary gland. Making a healthy clone from this cell was amazing. It proved that a cell from one body part could create a whole new animal. Ian Wilmut explained Dolly's name. He said, "Dolly is from a mammary gland cell. We couldn't think of a more impressive pair of glands than Dolly Parton's."
Dolly's Birth Story
Dolly was born on July 5, 1996. She had three "mothers" in a way. One sheep gave the egg. Another sheep provided the DNA. A third sheep carried the cloned embryo. This third sheep was like a surrogate mother.
Dolly was made using a method called somatic cell nuclear transfer. Here's how it works:
- Scientists took the center part (the cell nucleus) from an adult cell. This cell came from the udder.
- They put this nucleus into an egg cell. This egg cell had its own nucleus removed.
- The new cell was then given an electric shock. This made it start dividing.
- When it grew into a tiny ball of cells, it was put into a surrogate mother.
Dolly was the first clone from an adult mammal cell. Her birth showed that adult cells can be "reset." They can go back to an early state. This means they can then grow into any part of an animal.
Dolly's existence was announced on February 22, 1997. It caused a huge stir in the news. There were TV commercials and special reports. Science magazine even called Dolly the "breakthrough of the year." She got so much attention because she was cloned from an adult cell.
Dolly's Life
Dolly lived her entire life at the Roslin Institute. She was bred with a Welsh Mountain ram. She gave birth to six lambs in total. Her first lamb was named Bonnie. Bonnie was born in April 1998. The next year, Dolly had twins, Sally and Rosie. In 2000, she gave birth to triplets: Lucy, Darcy, and Cotton.
In late 2001, Dolly was four years old. She started to develop arthritis. This made her walk stiffly. She was given medicine to help with the pain.
Dolly's Passing
Dolly died on February 14, 2003. She had a serious lung disease. She also had severe arthritis. A sheep like Dolly usually lives for about 11 to 12 years. Dolly lived for 6.5 years.
After she died, doctors examined her body. They found she had a type of lung cancer. It is common in sheep. Scientists at Roslin said they did not think her being a clone caused this. Other sheep in the same group had also died from the same disease. Lung diseases are a risk for sheep kept indoors. Dolly had to sleep inside for safety reasons.
Some news reports wondered if Dolly died early because she was a clone. They thought she might have been "born" with the genetic age of the adult sheep she was cloned from. This idea came from finding that Dolly's telomeres were short. Telomeres are parts of DNA that get shorter as cells age. However, the Roslin Institute said that health checks showed no signs of early aging in Dolly.
In 2016, scientists studied 13 cloned sheep. Four of these were from the same cell line as Dolly. They found no major health problems in these older cloned sheep. They concluded that cloning did not cause long-term health issues.
After her death, Dolly's body was preserved. You can see her on display at the National Museum of Scotland in Edinburgh.
Dolly's Legacy
Dolly's success showed that cloning was possible. After her, many other large mammals were cloned. These included pigs, deer, horses, and bulls. Cloning can be difficult. In 1996, Dolly was the only lamb to survive out of 277 attempts. By 2014, Chinese scientists were much better at it. They had 70-80% success rates cloning pigs.
Cloning might help save animals that are in danger. It could even bring back extinct species. In 2009, scientists cloned a Pyrenean ibex. This wild mountain goat was declared extinct in 2000. The cloned ibex died soon after birth. But it was the first time an extinct animal had been cloned. This opens doors for saving endangered animals.
In July 2016, four sheep were alive and healthy. They were exact clones of Dolly. Their names were Daisy, Debbie, Dianna, and Denise. They were nine years old.
Scientific American said in 2016 that Dolly's biggest impact wasn't just cloning animals. It was on stem cell research. After Dolly, scientists learned that regular cells could be "reprogrammed." These reprogrammed cells are called induced pluripotent stem cells. They can be grown into almost any body tissue.
In 2018, the first primate (like monkeys and humans) was cloned. This used the same method as Dolly. Two identical macaque monkeys, Zhong Zhong and Hua Hua, were born in China. In 2019, scientists in China cloned five more monkeys. These monkeys were also gene-edited. This was done to study different medical diseases.
See also
- In re Roslin Institute (Edinburgh) – A US court decision about whether Dolly could be patented.
