Well, you learn something new every day. It turns out there
is actually a disease that is associated with a lack of
functional telomerase activity in cells. It is known as
"dyskeratosis congenita". Apparently this can by both defects
in the DKC1 gene (which makes dyskerin) as well as the
RNA component of the telomerase ribo-protein complex.
The features of the disease can be found here:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9886310&dopt=Abstract
The Nature article (subscription required) on the discovery
of defects in the RNA component of telomerase is here:
The RNA component of telomerase is mutated in autosomal dominant
dyskeratosis congenita
Tom Vuilliamy et al
Nature 413:432-435 (2001)
http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v413/n6854/full/413432a0_fs.html
A summary article that discusses the implications vis-a-vis aging is here:
Human genetics: Testing telomerase
Robert Marciniak and Leonard Guarente
Nature 413:370-373 (2001)
is here:
http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v413/n6854/full/413370a0_fs.html
It is clear that telomerase activity is important for the maintenance
of tissues in which cells undergo division throughout life such as
the bone marrow and gut but because lack of telomerase activity
does not result in symptoms that more closely resemble "natural"
aging, as is the case with Werner's Syndrome and Progeria,
it seems to be the case that telomeres are not involved so much
in aging as they are in the development (or prevention) of cancer.
Signs of the singularity: When it takes only 3(!) years from the discovery
of the DKC1 gene (1998) to the linking of it and related components
to telomerase activity and the determination of the role it plays
in the aging of some organ systems.
Interestingly enough, the fact that there is an classified clinical
disease here and the treatment would be well defined (to restore
telomerase activity in the tissues where it is normally present) --
is going to put a fair amount of pressure on clinicians to develop
gene therapy vectors that can restore telomerase function. Those in
turn may be useful for anti-aging therapeutics with a small amount of
tweeking (to restore telomerase function in other cells).
Robert
This archive was generated by hypermail 2b30 : Sat May 11 2002 - 17:44:11 MDT