Making a Mouse that Exhibits Human Telomere Dynamics

Telomerase acts to extend telomeres, the repeated DNA sequences at the ends of chromosomes. With every cell division, some of the telomere repeats are lost. Cells with critically short telomeres become senescent or undergo programmed cell death, having reached the Hayflick limit on replication. Some cells employ telomerase to adjust the countdown of telomere length. In humans, only stem cells use telomerase. In other species, such as mice, telomerase is much more widely expressed. There has been some interest in the research community in upregulation of telomerase as a way to improve stem cell and tissue function in old age. One of the points of risk in bringing telomerase gene therapies to the clinic is that while the results to date in mice have been impressive, gene therapies producing extended life, improved function, reduced cancer incidence, mice have very different telomere dynamics from humans. Will the risk of extending the functional life of damaged, potentially cancerous somatic cells be offset by improved immune function in humans as it seems to be in mice? While some number of people have undergone telomerase gene therapy, largely via medical tourism, results for most of those patients will never be published, and long-term data on cancer risk will in any case take years to emerge. In today's open access paper, researchers report on the development of a mouse lineage with a humanized telomerase gene and more human-like telomere dynamics. This will b...
Source: Fight Aging! - Category: Research Authors: Tags: Medicine, Biotech, Research Source Type: blogs