Dolly the Sheep is the first animal to ever be cloned from the cells of an adult. Even if 14 years have passed since she died, she is still making the headlines and keeping the scientists’ attention. They have long suspected that her death was the result of her being a clone, but a new study suggests she suffered natural levels of damage in her body for a sheep her age.
Dolly developed osteoarthritis at the age of 5
Scientists used somatic-cell nuclear transfer (SCNT) to create a completely new embryo from an adult cell. She was born in June 5th, 1996, and died on February 14th, 2003. Scientists decided to euthanize her after she contracted a deadly virus which affected her lungs.
However, when she was 5, she developed osteoarthritis, which affected her left knee. This led to dozens of ethical debates, as many said this happened due to the fact that Dolly was a clone. They blamed the process for making her age too quickly, and said cloning is not a viable practice. So many years later, researchers managed to prove that the aging wasn’t the result of cloning.
None of the cloned sheep showed abnormal aging signs
To prove their point, the researchers studied the remnants of Dolly, as well as the skeletons of several other sheep. Some of them were other sheep which were cloned, Morag and Megan, and another one was Dolly’s daughter, Bonnie, which she had given birth to naturally. After performing X-ray scans on their skeletons, they compared them with other non-cloned sheep.
They discovered that the cloned sheep exhibited no unnatural signs of aging. Although some of them developed osteoarthritis, this wasn’t uncommon for non-cloned sheep of a similar age. Also, apart from this condition, Dolly and the other clones were in perfect health. The study has been published in the journal Scientific Reports.
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