When the sheep dolly was successfully cloned, it was produced by growing an in vitro fertilized egg where the normal egg nucleus had been removed and replaced by a nucleus from an adult. since this nucleus is from an old mature animal, we would expect it to interestingly, tests show that this did not happen, a fact that currently puzzles researchers.

it is expected to have shorter telomeres

Explanation:

with aging, telomeres activities reduce resulting in shortening, thus, since the nucleus was replaced with an older one, it is expected that the telomeres length will shorten.

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link: