Longevity

So there's all kind of limits in our cells on how long they can live, and if we turn them off we'll be a walking bag of cancer in short order, right?

It would seem the only way of immortality is indeed through our children, but that's a poor trick at best. Continuity is key here, and preventing moments lost in time like tears in rain, etc., etc.

So we want to get some of the benefits of life on a macroscopic scale, like a flock of animals replaces and renews itself, to apply to our own internal cells. Offspring and change are central here.

I'm not thinking about something primitive like harvesting our children for organs. That's crude and intrusive, and of course hopeless when it's your brain that's going. I'm talking about growing fresh cells produced by sexual reproduction and injecting them into your body, making you an artificial chimera. You'd probably have to do some genetic engineering to make the immune systems totally compatible.

The idea would be for over 80% of your cells to be replaced by age 70 or so, ready to fill in when the cells with your original DNA start croaking of age and obsolescence. By then you'd probably have three to five different distinct DNAs in you, all mixed up. Change, with continuity.

Thoughts?

in after acid

You'd probably have to do some genetic engineering to make the immune systems totally compatible.
If by ``some'' you mean that you'd have to replace everything at once. Your body will not tolerate a foreign intruder. It has been developing mechanisms to fight them off for millions of years.

>>1
Why bother with a chimera, when you can just renew yourself?  It's not the DNA that's aging, it's the cells.  If you can generate new stem cells of your own, weed them for cancer potential, then have them integrate into your current system, you could probably live indefinitely.  You're still liable for cancer though.

The key difficulties are
a) "fresh" cells
b) randomly floating in your bloodstream won't do much good; they have to actually go to targeted locations

>>3
Just the bone marrow that produces WBCs.  As long as the WBCs tolerate whatever genetically engineered crap you inserted, the rest of the cells don't care.

>>4
Why bother with a chimera, when you can just renew yourself?  It's not the DNA that's aging, it's the cells.
Enjoy your vastly increased susceptibility to parasites and infection as you get older. That's the whole reason sex was invented.

>>3
I thought it'd be easiest to engineer the new cells so they'd look like your own cells by your immune system. They look at protein signatures and not the actual DNA, right?

>>4
Ah well, I suppose. It would be kind of romantic though, you could exchange traits with your partner. Imagine having orange hair from your redhead ex-wife.

>>6
They look at protein signatures and not the actual DNA, right?
How are you going to stop the DNA from manufacturing its own protein signatures to displace your artificial ones?

http://www.ted.com/index.php/talks/aubrey_de_grey_says_we_can_avoid_aging.html

>>5 It's not the DNA that's aging, it's the cells.

The DNA and RNA are the control circuitry for the cells.  Most somatotypes can still divide, but mutations and errors accumulate in the DNA year by year, decade by decade, until somewhere around threescore and ten at best, the machine fails catastrophically at one of many many many possible single points of failure, from pneumonia while bedridden from a fractured hip that crumbled like rotten paper-mache to cancer to a stroke.

>>5
Good point, but not dramatically important in the short term.

>>6
That'd be pretty awesome.  Nice imagination, anon!

>>7
Controlling MHC I is going to be hard...

>>9
I forgot about DNA/RNA errors/mutations.  However, I think fixing those problems is a given if we have (advanced) genetic engineering.  Pneumonia is probably unrelated.

>>10
Good point, but not dramatically important in the short term.
Bullshit. If it weren't, generations would be a lot longer than they currently are.
Disease is still far and away the most important cause of death in the world, not age. Don't underestimate its potency, and don't hope modern medicine can keep up.

>>11
The purpose of modern medicine is not to keep up. It's always straggling its fuckin' ass behind.

>>12
Kind of true. Your probability of pulling trough any one particular disease seems to be rising steadily, but when you look at how technology and science has progressed, the increases we have seen in average life expectancy seem relatively meager.

We are getting a deeper understanding of molecular interactions and exponentially more computing power to play around with, we have gotten better manufacturing techniques both for medicine and for surgical equipment. Previous known instrument have become cheaper and lighter, and supplemented by expensive new ones. Why aren't we gaining a deep enough understanding of our biology to create and modify it at will?

>>11
Actually, looking at the statistics for the U.S., at least, heart disease is the country's major killer, followed by cancer. These are both diseases that mostly befall the elderly, especially heart diseases. Cancer is somewhat more even-handed, but you have a much better chance of pulling through if you're otherwise healthy. If we could make the elderly just a bit less elderly-like, life expectancy would shoot through the roof. I'm not doubting that in the world at large, disease, famine and war kills a depressingly large amount of people, but those now have apparent and uninteresting solutions in the hard sciences, and are waiting for macroeconomics and politics to catch up.

There's a couple of years to be gained by improved diet and fitness, but even the best countries currently have a quite unspectacular lead over the U.S., which is generally regarded as something of a slob.

>>13
but when you look at how technology and science has progressed, the increases we have seen in average life expectancy seem relatively meager.
I wouldn't call a quadrupling of the average life expectancy meager.

Why aren't we gaining a deep enough understanding of our biology to create and modify it at will?
For the same reason nanotechnology is challenging, except that with nanotechnology, you don't also have to deal with an environment actively trying to break down your technology.

Actually, looking at the statistics for the U.S., at least, heart disease is the country's major killer, followed by cancer.
Both heart disease and cancer are umbrella terms for a vast number of wildly different afflictions.

>>13
sci/tech is mostly improving the life expectancy of middle aged - older people.  Young people are still drinking and driving, and getting themselves killed (among other accidental, but preventable forms of death, such as AIDS).

>>14
Current life expectancy is ~ 75 yrs or so, maybe 80.  A quarter of that is < 20.  Are you comparing now to over 9000BC?

I thought heart disease mostly comprises myocardial infarctions, stroke, and congestive heart failure.  I wouldn't call 3 "vast".

>>15
Current life expectancy is ~ 75 yrs or so, maybe 80.  A quarter of that is < 20.  Are you comparing now to over 9000BC?
Life expectancy around the first agricultural revolution was about 20, yes.

I thought heart disease mostly comprises myocardial infarctions, stroke, and congestive heart failure.  I wouldn't call 3 "vast".
Myocardial infarction can have any of a wide variety of varying causes, including disease. Same for congestive heart failure. Strokes affect the brain, not the heart, and are again an umbrella term.

>>15
(among other accidental, but preventable forms of death, such as AIDS)
All diseases are preventable if you lock yourself in a sterile basement.

ITT: ppl try to sound smrt

>>16
Life expectancy around the first agricultural revolution was about 20, yes.
Orly

Heart disease is pretty generic, and I always thought it included stroke; guess not.  Yes, I am aware that stroke affects the brain.

>>17
cancer

>>1
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>>10
    Tyrell: I'm surprised you didn't come here sooner.
    Roy: It's not an easy thing to meet your maker.
    Tyrell: What can he do for you?
    Roy: Can the maker repair what he makes?
    Tyrell: Would you like to be modified?
    Roy: I had in mind something a little more radical.
    Tyrell: What seems to be the problem?
    Roy: Death.
    Tyrell: Death. Well, I'm afraid that's a little out of my jurisdiction, you...
    Roy: I want more life, fucker/father.
    Tyrell: The facts of life: To make an alteration in the evolvement of an organic life system is fatal. A coding sequence cannot be revised once its been established.
    Roy: Why not?
    Tyrell: Because by the second day of incubation, any cells that have undergone reversion mutations give rise to revertant colonies like rats leaving a sinking ship; then the ship sinks.
    Roy: What about EMS recombination?
    Tyrell: We've already tried it. Ethyl methane sulfonate is an alkylating agent and a potent mutagen. It created a virus so lethal the subject was dead before he left the table.
    Roy: Then a repressor protein that blocks the operating cells.
    Tyrell: Wouldn't obstruct replication, but it does give rise to an error in replication so that the newly formed DNA strand carries a mutation and you've got a virus again. But this - all of this is academic. You were made as well as we could make you.
    Roy: But not to last.
    Tyrell: The light that burns twice as bright burns half as long, and you have burned so very very brightly, Roy. Look at you. You're the prodigal son. You're quite a prize!
    Roy: I've done questionable things.
    Tyrell: Also extraordinary things. Revel in your time!
    Roy: Nothing the god of biomechanics wouldn't let you into heaven for.

I'm a little surprised that no one posted this.