After the cloning of Dolly the sheep (the first cloned sheep) 20 years ago this July, the possibility of using this technique to obtain animals that could be exploited for ethically sound purposes has been suggested. However, one problem that has arisen is that Dolly, it seems, suffered premature aging and in turn was diagnosed with osteoarthritis at 5 years old, which made scientists think that the age of the sheep was not her biological age, but that which would correspond to her mother from which udder cells were obtained and used for the cloning. Now, in a study published in Nature Communications, it has been confirmed that 4 clones of Dolly, exact copies of the sheep, created at Nottingham University (United Kingdom), do not have arthritis, cardiovascular complaints or any other disorder that is not consistent with their age of 8 years old. This undoubtedly opens an attractive field for producing cloned animals that can be used with ethically acceptable ends (read China factory).

Photo: https://www.engadget.com/2016/07/27/dolly-sheep-clones-are-healthy/