Related Experiment Video
Updated: Jul 16, 2026

Telomere Length and Telomerase Activity; A Yin and Yang of Cell Senescence
Published on: May 22, 2013
Analysis of telomere length in Dolly, a sheep derived by nuclear transfer
P G Shiels1, A J Kind, K H Campbell
1PPL Therapeutics, Roslin, Midlothian, Scotland.
Abstract:
We have used a (TTAGGG) oligonucleotide probe to demonstrate that ovine telomeres are composed of (TTAGGG) repeat arrays and to compare the terminal restriction fragment lengths of sheep derived by natural mating and nuclear transfer. Here we show that ovine somatic telomeres decrease in length with age, and that Dolly, derived by the transfer of 6-year-old adult somatic nucleus, exhibits diminished terminal restriction fragment lengths. The decrease is consistent with the age of the donor tissue and telomere erosion during in vitro culture. Nuclear transfer does not restore telomere lengths. Dolly otherwise appears physiologically and phenotypically normal for her breed and age. We further report on apparent telomere lengthening in sheep, occurring during the first year in naturally derived lambs.
Related Concept Videos
Replication in Eukaryotes
Reproductive Cloning
Somatic Cell Nuclear Transfer
In SCNT, an egg cell is taken from an animal and its nucleus is removed, creating an enucleated egg. Then a somatic cell—any cell that is not a sex...
Telomeres and Telomerase
Replication in Eukaryotes
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...
Introduction to Nuclear Reprogramming
Cloning of Dolly the Sheep

