The enzyme telomerase has been shown to be present in immortal
cell lines. However, it has never been purified and therefore it has
never been cloned.
The average length of telomeres in dividing normal,
untransformed cells has been shown to shorten as the cell culture ages.
That is, there is a correlation between the length of the average
telomere size and the age of the culture.
The predictions of what the re-introduction of a telomerase
enzyme might do in ageing cells requires the cloning of the gene for
this enzyme. This is proving a very difficult task.
In presence it should be possible to reactivate the expression
of this gene in normal cells, and to repress its expression in cancer
cells, but this also awaits the cloning of the gene.
This area is therefore both very active and very excitibg, and
there is lots of room for more people in this field.
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