Telomere & Life Expectancy Link Found

Admiral Valdemar · Post by **Admiral Valdemar** » 2003-05-22 07:49am

Just reading the latest issue of New Scientist and come across an article showing that telomeres infact do have a relation to total life expectancy.

It also goes on to say that telomerase, the enzyme that repairs telomeres as they shorten after every cell replication cycle, is switched off most of the time as an anti-cancer mechanism since cancer cells never undergo senescence (programmed cell death).

I'll type up the article after my lectures if anyone wants it.

InnerBrat · Post by **InnerBrat** » 2003-05-22 07:53am

*hands up*
yes please.

kojikun · Post by **kojikun** » 2003-05-22 08:28am

thank you, this has been known for about a decade. theyve made various things live full unaged lives for 5 times their expected lifespan. but this is old news and has been brought up before here on SDN.

Admiral Valdemar · Post by **Admiral Valdemar** » 2003-05-22 12:45pm

kojikun wrote:thank you, this has been known for about a decade. theyve made various things live full unaged lives for 5 times their expected lifespan. but this is old news and has been brought up before here on SDN.

Actually it's new news since the study proves this point, before we only assumed this was a possibility.

I shall type it up later tonight, I'm going into town to see Tha Matrix with some mates later.

Admiral Valdemar · Post by **Admiral Valdemar** » 2003-05-22 02:14pm

Cracking the DNA link to lifespan

A direct link has at last been found between an animal's lifespan and the size of DNA sequences called telomeres in their chromosomes. But contrary to expectation, it's the rate at which telomeres shorten that matters, rather than their length. The finding is important because telomeres play a key role in cancer and ageing.

Telomeres are repetitive DNA sequences found at the ends of every chromosome. They normally shorten each time a cell divides. When they become too short the cellstops dividing and eventually becomes moribund. So telomere length sets an upper limit on the number of divisions a cell can undergo.

But while this link to cell lifespan and ageing is well established, researchers have had great difficulty linking telomere length directly with an organism's lifespan. Now new research suggest they were measuring the wrong thing.

Mark Haussmann and Carol Vleck at Iowa State University in Ames collected blood samples from birds of known ages and recorded the telomere lengths in DNA from the bird's red blood cells. They looked at five species of each with a different lifespan, and calculated the number of base pairs lost by the telomeres each year.

The researchers found the rate of telomere change per year, rather than overall telomere length, is an excellent predictor of the mazimum lifespan. And in one long-lived species, the Leach's storm-petrel, telomere length increased with age, the first time this has been observed, they will report in a future issue Proceedings of the Royal Society B.

The relationship holds true in mammals, as the researchers found when they analysed data from the scientific literature on eight mammal species. "The idea that you come up with the same slope is rather remarkable, says Bret Weinstein at the University of Michigan, Ann Arbor, who studies the links between telomeres, cancer and ageing.

Weinstein believes the results are evidence of a fundamental trade-off faced by mammals and birds. For if simply adding to telomeres extends lifespan, natural selection should have tended to lengthen them, especially as the enzyme telomerase, which rebuilds telomeres, is found in many different animals.

But other studies have linked telomerase activity to cancer. To continue dividing beyond their normal limits, cancer cells have to switch on the enzyme to prevent telomeres getting any shorter.

Setting a limit to the number of cell divisions, and switching off telomerase, are probably important anti-cancer mechanisms, says Weinstein. Creatures may make a different trade-off depending on their specific environment and ecology. James Randerson

-New Scientist No2396

So you see, I was right about us having evolved the whole concept of death.

kojikun · Post by **kojikun** » 2003-05-22 05:42pm

DRATS! FOILED AGAIN!

:p

Darth Servo · Post by **Darth Servo** » 2003-05-22 07:07pm

I knew about that stuff 7 years ago in my senior year of college. Course I did major in biology so I would have a head start over the general population.

phongn · Post by **phongn** » 2003-05-22 07:13pm

Unsuprising for those of us who have an inkling of Biology knowledge

HemlockGrey · Post by **HemlockGrey** » 2003-05-22 07:26pm

I think I've got about 60 years left. Plenty of time for them to perfect this things.

Admiral Valdemar · Post by **Admiral Valdemar** » 2003-05-22 08:36pm

HemlockGrey wrote:I think I've got about 60 years left. Plenty of time for them to perfect this things.

Well there is always the "million heartbeats" limit too.

EvilGrey · Post by **EvilGrey** » 2003-05-22 09:15pm

Admiral Valdemar wrote:
HemlockGrey wrote:I think I've got about 60 years left. Plenty of time for them to perfect this things.
Well there is always the "million heartbeats" limit too.

I'm sure they'll find ways to resolve that problem too.

May I live forever!

Shinova · Post by **Shinova** » 2003-05-22 09:22pm

So one thing we should do to achieve immortality is to cease the shortening of telomeres?

BWAAHAHAHAHAAAAA!!!!

Admiral Valdemar · Post by **Admiral Valdemar** » 2003-05-22 09:32pm

Shinova wrote:So one thing we should do to achieve immortality is to cease the shortening of telomeres?

BWAAHAHAHAHAAAAA!!!!

What exactly is it you find so funny?

HemlockGrey · Post by **HemlockGrey** » 2003-05-22 09:54pm

Well there is always the "million heartbeats" limit too.

They invented transplants for a reason.

Admiral Valdemar · Post by **Admiral Valdemar** » 2003-05-22 09:58pm

HemlockGrey wrote:
Well there is always the "million heartbeats" limit too.
They invented transplants for a reason.

Bah.

What if your brain can only do a million thoughts then it claps out?

Christ, I have less than a day left and DarkStar has till next millenium!

HemlockGrey · Post by **HemlockGrey** » 2003-05-22 10:00pm

You're just jealous of my youthful vigor and potentional immortality.

Admiral Valdemar · Post by **Admiral Valdemar** » 2003-05-22 10:05pm

HemlockGrey wrote:You're just jealous of my youthful vigor and potentional immortality.

*Fwip!*

Nah.

*Holsters silenced handgun*

FireNexus · Post by **FireNexus** » 2003-05-23 12:35am

Admiral Valdemar wrote:Bah.

What if your brain can only do a million thoughts then it claps out?

Christ, I have less than a day left and DarkStar has till next millenium!

Come on, Val, be realistic. If you go by that, then DarkStar should be around when the sun winks out.

Edit: Fixed the quote.

Shinova · Post by **Shinova** » 2003-05-23 01:15am

Admiral Valdemar wrote: What exactly is it you find so funny?

It's my insane maniac laugh.

Basically I'm saying yay for progress toward immortality.

Admiral Valdemar · Post by **Admiral Valdemar** » 2003-05-23 07:56am

Shinova wrote:
Admiral Valdemar wrote: What exactly is it you find so funny?
It's my insane maniac laugh.

Basically I'm saying yay for progress toward immortality.

Yay for immortality!

His Divine Shadow · Post by **His Divine Shadow** » 2003-05-24 11:16am

Admiral Valdemar wrote:
HemlockGrey wrote:I think I've got about 60 years left. Plenty of time for them to perfect this things.
Well there is always the "million heartbeats" limit too.

Given the speed of which artificial hearts are evolving I think they'll have a pretty good replacement withing 20-30 years.

SyntaxVorlon · Post by **SyntaxVorlon** » 2003-05-24 11:59am

That or we'll start genofixing.

Who need 5000 years of space travel and technological development, I wanna live for 400 years NOW!