5 ms·

One thing I'd really like to understand re: ageing is why a newborn is essentially 'reset' from an ageing perspective. I appreciate that egg cells aren't consta

One thing I'd really like to understand re: ageing is why a newborn is essentially 'reset' from an ageing perspective. I appreciate that egg cells aren't constantly dividing during a mothers life but they are still a product of division and contain DNA that can suffer from time based mutations. So if aging is due to mistakes accumulated during either divisions or time then why are children born young? I don't think this is as simple as non-viable embryos are miscarried, there must be something different in the formation of embryos that means they don't carry the aging of their parents...and what clue does that give to cure aging?

X4 13y ago
Correct me if I'm wrong, I'm not a geneticist, but the logical reason for this sounds as simple as enriching the baby's DNA with that from the mother and father. Also only cells, which are our main building blocks, suffer from death. The death as we know it, is only affecting "bodily" species incl. single-celled life forms. DNA doesn't die, ever (given good conditions). That's why scientists can still extract DNA from animals which have been died thousands or millions of years ago.
hughlomas 13y ago
The organism is a vessel to propagate the genes. Germ cells such as embryos usually have additional defenses and repair mechanisms, such as for DNA damage, that the somatic cells lack. Since the soma are merely there to help the replication of the germ line, they receive less investment. No creature we know of has successfully evolved the capability to permanently stave off aging. Besides the inevitable issues with fighting entropy in a complex system, how would an ageless organism compete in the shifting landscape of an ecosystem as other creatures evolve around it? How would a non-aging organism adapt? It seems likely that continually creating new generations is the best strategy for genetic replication. Now we are at the amusing point that genes may have unwittingly experienced their own skynet event. Modern science has given us the ability to not only gaze upon our creators, but manipulate them to do the bidding of ideas.
- simonsquiff 13y ago
  Thanks - germ cells was the key term I was missing, this section on the germline on Wikipedia answers my original question: Germline cells are immortal, in the sense that they have reproduced indefinitely since the beginning of life. This is largely due to the activity of the enzyme known as telomerase. This enzyme extends the telomeres of the chromosome, preventing chromosome fusions and other negative effects of shortened telomeres. Most somatic cells, by comparison, can only divide around 30-50 times according to the Hayflick limit. Certain somatic cells, known as stem cells, also express telomerase and are potentially immortal.
  - Houshalter 13y ago
    So then why can't we just inject ourselves with that enzyme and be immortal?
- eli_gottlieb 13y ago
  >Now we are at the amusing point that genes may have unwittingly experienced their own skynet event. Modern science has given us the ability to not only gaze upon our creators, but manipulate them to do the bidding of ideas. Come on, man. Laugh maniacally! You know you want to. Here, I'll start: MUWWWWWAUAUAHAHAAHAHAHAAAAA AAAAAAAAAAAAAAAHAHAHAHAHAAAAAAAAAA!!!!!!!!!!!!!!

X4 13y ago

Correct me if I'm wrong, I'm not a geneticist, but the logical reason for this sounds as simple as enriching the baby's DNA with that from the mother and father. Also only cells, which are our main building blocks, suffer from death. The death as we know it, is only affecting "bodily" species incl. single-celled life forms. DNA doesn't die, ever (given good conditions). That's why scientists can still extract DNA from animals which have been died thousands or millions of years ago.

hughlomas 13y ago

The organism is a vessel to propagate the genes. Germ cells such as embryos usually have additional defenses and repair mechanisms, such as for DNA damage, that the somatic cells lack. Since the soma are merely there to help the replication of the germ line, they receive less investment. No creature we know of has successfully evolved the capability to permanently stave off aging. Besides the inevitable issues with fighting entropy in a complex system, how would an ageless organism compete in the shifting landscape of an ecosystem as other creatures evolve around it? How would a non-aging organism adapt? It seems likely that continually creating new generations is the best strategy for genetic replication. Now we are at the amusing point that genes may have unwittingly experienced their own skynet event. Modern science has given us the ability to not only gaze upon our creators, but manipulate them to do the bidding of ideas.

simonsquiff 13y ago
Thanks - germ cells was the key term I was missing, this section on the germline on Wikipedia answers my original question: Germline cells are immortal, in the sense that they have reproduced indefinitely since the beginning of life. This is largely due to the activity of the enzyme known as telomerase. This enzyme extends the telomeres of the chromosome, preventing chromosome fusions and other negative effects of shortened telomeres. Most somatic cells, by comparison, can only divide around 30-50 times according to the Hayflick limit. Certain somatic cells, known as stem cells, also express telomerase and are potentially immortal.
- Houshalter 13y ago
  So then why can't we just inject ourselves with that enzyme and be immortal?
eli_gottlieb 13y ago
>Now we are at the amusing point that genes may have unwittingly experienced their own skynet event. Modern science has given us the ability to not only gaze upon our creators, but manipulate them to do the bidding of ideas. Come on, man. Laugh maniacally! You know you want to. Here, I'll start: MUWWWWWAUAUAHAHAAHAHAHAAAAA AAAAAAAAAAAAAAAHAHAHAHAHAAAAAAAAAA!!!!!!!!!!!!!!