Abstract: Telomeres are composed of repeated DNA sequences and specific DNA-binding proteins, which form a nucleoprotein complex at the end of eukaryotic chromosomes, and play an important role in the replication and stability of the telomeres. Recent researches indicate that telomere-shorten is closely related to disease and aging of the human. Being considered as an available instrument of agamogenesis, somatic cell nuclear transfer (SCNT) is widely applied in research and production. However, restricted by the fact that donor cells are always adult somatic cells, which contain shortened telomeres, it is significant to ensure whether telomeres of cloned animals are restored in the embryogenesis or not. In this article, authors review the latest researches about the structure of telomere, telomere maintain mechanism and telomere length of cloned mammals.

Key words: telomere; telomere length; mammal; somatic cell nuclear transfer