Reply to Thomas

Thomas Mahoney excelife at
Fri Apr 16 09:13:05 EST 1999

In article <199904131901.MAA18485 at>, lolo-xtc at PULLMAN.COM 
>Thank you for those references!
> I had a look at them and it is interesting but by no means conclusive.

I quite agree.  They are suggestive that telomeric maintenance may be related 
to organismal life span but much research needs to be done to determine what 
effects, if any, the telomerase is having on the non-replicating cells in 
these animals.

> The fact that telomerase is active in the tissues of those organisms is,
>in my opinion, no proof that telomere shortening is causing aging in vivo.

Yes, all we have here is a correlation and need to understand the science to 
determine if there is a valid link.

>The key word is that those organisms have indeterminate growth, meaning
>that they grow continuously throughout their lifespan.
>The rattle snake is such an example. A colleague here at my University
>studies rattlesnakes and they too have inditerminated growth. Also, just
>like the lobster and rainbow trout, they do not exhibit senescence in the

It is predictable that many of the cells in these animals, as well, will show 
active telomerase functioning.

However, their maximum lifespan in only 17 years and they also
>exhibit mortality rate doublings when in captivity (i.e. senescence). And I
>bet you they have active telomerase in their somatic cells as well. So my
>point is, that while active telomerase may be required for indeterminate
>growth, it does not seem to be correlated with lifespan.

There are many causes of death completely unrelated to telomeric length and 
telomerase activity. Some people claim there are none:-(  I would suggest 
that telomeric length does have an impact on the maximal lifespan of these 
animals but that death and mortality rates would vary, as you noted above, 
based on numerous other variables. 
> Here is what it would take to swing my opinion. If you could show that a
>transgenic animal overexpressing telomerase in somatic tissues has
>increased maximum longevity, perhaps only as much as 10%, I think I would
>be convinced.

That is, of course, the goal of much of this research.  Experiments on marine 
animal closely related to the rainbow trout and the lobster may just show 
such results.  Whether these results would be applicable to mammals and other 
higher organisms is still to be determined. 

>And I would really love for you to publish that. I have stock
>in Geron, for reason not directly related to telomerase, and I know the
>stock would be shooting up as soon as you announced such a finding.

Geron does have a wide range of research projects in the works, many of them 
in co-operation with some of the finest research labs. in the Nation. 
Hopefully some of this work will be published in the coming Months. 

>So get to work! =)

We are doing what we can:-)

Thomas Mahoney, Pres.
Lifeline Laboratories, Inc. 

More information about the Ageing mailing list