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Science

Cloned sheep shows signs of premature aging 99

Posted by Hemos from the dolly-we-hardly-knew-thee dept.
Wonko42 writes "Everyone's favorite cloned sheep, Dolly, is showing signs of premature aging. Even though she's only three years old, her cells are acting like they're six years old. Scientists think this is because she was cloned using cells from an older sheep. "
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Cloned sheep shows signs of premature aging More

Cloned sheep shows signs of premature aging

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  • Not that much of a problem. (Score:1)

    by Anonymous Coward
    Preventing telomere shortening doesn't do much for you when you hit a brick wall at 90 mph. Nor does it stop you from dying of disease. Is old age even a leading cause of death? I'm sure it must be up there, but death won't vanish along with old age. Various age related illnesses probably won't vanish either. For example, regardless of how long your cells themselves live, human beings don't exactly heal very well. Break a bone, dislocate a joint and, even though they "heal" they don't do it perfectly and leave traces that last a lifetime, cell aging or no cell aging. Aging makes them much more noticable, to be sure, but after two hundred, three hundred years of being a twenty year old on a cellular level won't you be starting to be just a little too made up of scar tissue? And what about things like plaques in your arteries? Won't they build up pretty heavily too? Aren't there a lot more things that can go wrong with your body than pre-programmed cell death?
    Anyway, there's a lot more than telomeres to sort out before we become functionally immortal (amortal? we wouldn't be incapable of dying, it just wouldn't happen from old age). I personally think we will get there, and I hope I'm alive to see it.
    As far as overpopulation goes, we already seem to be possibly heading for a nasty crunch as far as that goes. By the time we have the means to make ourselves immortal, hopefully the birthrate will have balanced out to something sane. As long as it doesn't outstrip the deathrate (which will never dwindle to nothing) things should be ok.

  • Re:drowning in our own shit (Score:1)

    by Anonymous Coward
    No, he is not right. How many people the planet can handle has very little to do with how long people live. (People have been living to 70-odd years for a fairly long time now anyway.) The young, and not the old, are the ones who have the long-term effect on the earth. When "primitive" people have needed to keep their population down, they have done it by infanticide; geronticide is virtually unknown. When you bump off an old person, you reduce the load by...one person x however many more years that person was going to live. When you bump off a young person, you reduce the load by one person x however many years of life PLUS their potential offspring. Reproduction rate, and not age at death, is what causes the load.

  • Re:Not completely Off-Topic (Score:1)

    by Anonymous Coward
    I really think that the fears over population are rather misplaced. Read PJ O'Rourke's All The Trouble In The World some time. It's extremely flippant, but nonetheless makes some excellent points about population and wealth. For example, Bangladesh is popularly perceived as an overpopulated hellhole. But Bangladesh's population density is the same as that of Fremont, California, and pretty much nobody regards Fremont as a disaster zone. Furthermore, as he points out, the Bangladeshis must be doing something right at some level - 11 million people (and growing) don't live in a place just because it's a horrible pit of despair and they're all masochists. We really know very little about the connection between population and well-being: Hong Kong is crowded and rich, Bangladesh is crowded and poor; Canada is empty and rich, Chad is empty and poor.

    On a related note, it's highly unlikely - virtually impossible - that we will ever "run out" of land or natural resources. As a resource (the amount of which is relatively stable) becomes more in demand, the price rises. This has several effects: firstly, it tends to discourage use of the resource, secondly, it encourages increased investment in finding more of the resource, and thirdly, it increases interest in finding alternate resources. Take energy as an example. In Europe, energy (non-muscle energy, anyway) used to pretty much all come from burning wood. But the demand for wood caused deforestation, and people switched to the more plentiful and cheaper peat moss. That didn't last long before people switched to the more plentiful and cheaper whale oil, and then in turn to coal, and then oil. Note that we never switched because we "ran out" of wood, peat moss, or whales. You still find all of these things around. Likewise, it's highly unlikely that we'll ever "run out" of oil; as the supply dwindles, the demand increases, and the cost of finding more goes up, alternative energy sources will become more and more appealing, and eventually we'll switch to something else...and there will still be oil left when we do so, but it won't matter much anymore, because it will have become as irrelevant as peat moss is today. And note that this is not a history of people painfully dragging themselves from dying energy source to ever smaller dying energy source - we do a whole lot more with oil than we ever could have with wood or peat moss. The proper response to anyone who warns you to conserve energy, so our descendants will have lots left, should be to imagine an 18th century European warning you to conserve whale oil, so our descendants will have always enough whale oil left to run their great civilizations on.

  • Not genetically modified. (Score:2)

    by Anonymous Coward
    The sheep is a clone. The whole point is that it has the same DNA as the original. No DNA modification involved.

  • Just wait until she metamorphoses! (Score:2)

    by Anonymous Coward
    When those telemeres finally run down, the REAL Dolly -- a 18' tall bloodthirsty creature with poison-dripping fangs and glowing red eyes -- will tear its way out of the carrier-sheep's gentle-seeming carcass and cut a bloody swath through the scottish moors.

    At least, that's how I learned how things work from horror movies.

  • Re:clarify your number, please (Score:2)

    by Anonymous Coward
    7x10^5? What does this refer to? The average human cell can divide 50 (+/-10) times before dying (undergoing apoptosis to be technical).

    All the numbers I have seen are in this range (around 50), but keep in mind that they are for cells in a culture dish, not cells in the body... and of course there is a fair degree of variation among cell types.

    I don't think we've had immortal eukaryotic cell lines for 80 years, but I could be wrong. Where did that number come from? This is not intended as flamebait. I'm just curious.

    That number has to be bogus, as you've alluded to with your calculation. I think the HeLa cell line goes back to the 60s or 70s.

    Another way of looking at this number is to realize that if a cell can divide 7e+5 times then you would end up with 2^7e+5 cells. I don't have a calculator on hand that can deal with a number this big, but approximating 2^4 = 10 (a nice margin of underestimation), that converts to about 1e+17500.

    Assume that the average cell is a cube 20 microns on a side, or 8e-15 cubic meters each. Then the volume of all these cells is approximately 1e+17486 meters cubed! A sphere of this volume would have diameter well in excess of 1e+5700 kilometers.

    A light year is about 9e+12 kilometers, so this sphere of cells would have a diameter of well over 1e+5600 light years!

    I suspect that this is larger than the estimated size of the universe, but I don't have a hard figure there. I do know that my physics text says that we can see quasars up to 1e+10 light years away.

    Those exponents sure do balloon quickly.

  • Interesting point. But wouldn't it just be like having offspring when one is older in life. If someone sired offspring when they were 70 would their offspring have an older "genetic age"? I don't think so. The only problem that I can see is that Dolly may reach an age where she is too old to have offspring- three years earlier!

  • The age of cells (Score:5)

    by MacJedi ( 173 ) on Thursday May 27, 1999 @05:35AM (#1877742) Homepage

    Its been known for some time now that most cells don't live forever. I think it has actually been calcualted that human cells will only devide X numer of times before they stop working very well (where X is a number around 7x10^5 or so).

    Some cells don't have this problem- noteably stem cells (the cells in your bone marrow from which all other cells come from) and cancerous cells. (!!!) I would have thought that Dolly would have been cloned from a stem cell. Maybe this was not possible when she was, uh, created.

    The part of the article about telomeres is fairly accurate. Due to the way that DNA replicates, the ends of the chromosomes are not copied properly. There is an enzyme called telomerase that adresses this problem by capping the ends of the chromosome on each replication. (This also keeps the ends of the DNA from being degraded by enzymes in the cell's endoplasm). But telomerase doesn't do its job perfectly and the chromosome eventually starts to loose important parts of its DNA. How or even if this then triggers a self-destruct process in the cell is not really understood. Perhaps cloning can be used to study this.

  • Well, from what I understand, the actual genetic material from the cells is NEVER damaged at all, only "redundant" (to the protein syntesis) parts of the DNA string are "eaten up" during mitosis (cell division), which is what the telomers are.
    So, eventually, the cell dies.

    However, during meiosis (which is when the cells divide to form the gametes), the telomeres are probably regenerated, which is why the offsprings live the normal age excpected for the species.

    This would also happen when mating two cloned, as when producing the gametes, the genetic machinery from those animals would also fix the telomers of the cromossomes, thus making a perfectly fine offsrping.
  • I very much doubt you could be cloned from tooth enamel. The required genetic material to be copied is just not in. You need _cells_, though remnant nerve cells in the base might be slightly viable..
  • >It's a copy. Every time you make a copy the quality degrades.

    And then there's those MP3 clones. Some people think they're just about as good, others can't stand 'em. But you can fit 10 times as many in the same space!
  • This seems to reinforce the idea that there are "time bombs" in cells that cause the aging/death process. It may also be possible to extrapolate that something in the genetic material has "programmed" the apparent age.


    This is interesting. This may make it easier to scientists to isolate the part of the genes that cause us to grow old and die aftet about 80 years. Living longer not only will improve our life (we get smarter and gain more experience as we grow older), but we will be forced into looking for more places to habitate, i.e. space travel. As people live longer and more people are born, this planet does not have the capacity to sustain us all, unless we stop having babies (not probable). The prospect of living longer will be a boon to those setting out on super long missions to other stars in search for planets to inhabit. In the meantime, Mars should hold us over for some time ;).
    It's far easier to forgive your enemy after you get even with him.
  • >But wouldn't it just be like having offspring
    >when one is older in life.

    That's the crux of it, I think. Where I see the problem is that that 70 year old started out with "correct" material to form the gametes, and "corrects" to that. But the clone doesn't get that, so do the sexual organs correct to the right value, or do the correct to what they started with?
  • The article claims that she started with over-aged cells, and thus "inherits" this agge, but that her offspring would be normal. But would they? This would require some type of "repair" of here gametes, as her ovaries will have been formed from the wrong "age" of cells. Even presuming something about ovaries and testes that avoids the general agin effect, might this only fix cells to the age of those (normally a couple of days) forming the organs?

  • . . . those damn crazy monkeys thought they were so smart. . .




    "The number of suckers born each minute doubles every 18 months."
    -jafac's law
  • This was a topic in a recent Time (or Newsweek?) and Popular Science. Basically, all the over-use of antibiotics has begun to breed antibiotic-resistant bacteria. Penicillin doesn't work as well as it did, and many of the other common antibiotics aren't, either. What's worse about this is that it isn't just use of antibiotics on people, it's use on livestock, too. Very big argument for proper food preparation. It's also been suggested that such behavior by parents leads to lower resistance to even minor things in their children, where a lack of exposure to common germs and particles at a young age leading to allergies and such later in life.

    Very War of the Worlds (wasn't it?) kind of thought: being killed by the common cold.
    --
  • To *cure* aging, we'll probably have to find a way to repair or replace cells which wear out, on a case-by-case basis. This could be anything from low-level repair via nanotech, to body-swapping (brain included) every half-century.

    If evolution tries to perfectionize nature, and human beings are part of it, life itself should have provided such a mechanism: Reincarnation; sooner or later all of us will realize if it's true or false.

  • Other Considerations (Score:5)

    by Hrunting ( 2191 ) on Thursday May 27, 1999 @03:06AM (#1877752) Homepage
    The article points out that this may cause the sheep to die earlier than expected as all the cells are older. I would think that there would be other complications (or benefits) as well. As people age, their metabolism slows down. They also get wrinkly, smell funny, and go bald. Cloning of animals may finally help us to understand how aging works. Is it a result of time upon the body, or is it a result of genetics? We may even get some medical benefits as the body fights disease differently with age and we could start people off at an optimal age for immune system development (not being a doctor, this may well be birth).

    And if humans are ever cloned, what does this mean for things like Senior Citizen discounts and Social Security (I know this doesn't necessarily apply outside of the US). Is someone 65 years old because they've been on this planet for 65 years or because their cells say they're 65? Perhaps these old people who are climbing mountains and water skiing barefoot on one leg aren't really old, they've just been around for a while. :)
  • Well, first of all, those nations that have a higher dependence on advanced technologies (including medicine) also have a lower birthrate. If this trend were to continue, it's possible that the birthrate wouldn't be much higher than a deathrate from accidents, suicide, and homocide.

    Further, I'm also confident that by the time we have the ability to significantly extend human lifetime with better medicine, we'll also have the ability to easily expand beyond this planet and begin to live in space or on other worlds.

  • I thought it was a joke at first, too. But it seems Seed, who is a physicist by training, is trying to talk investers into funding a cloning project intended to allow couples with fertility problems to clone one or the other parent and bring the clone to term as a baby.

    It's a strange world where a man named Dick Seed could get involved in reproduction!

  • This is interesting. I have been watching and commenting on Dolly ever since she was announced. At my website, I have a small section devoted to her and even warned about the possibility that something along these lines, [cris.com] a sort of sheep progeria, might strike her.

    I wonder now what impact this will have on Richard Seed's infertility work...

  • You're spot on. My wife (internal medicine physician) tells me we're already seeing the following adaptation: richer people have been demanding (and getting) antibiotics for just about everything, including minor viral ailments where antibiotics don't do any good...but the loud, litigious rich folks with a sense of supreme entitlement push and scream, and so many docs give them the antibiotics they demand. So...over time these richer folks have become "immuno-compromised", so that if they have a REAL infection, sometimes they get really sick (and even die) because their virii and bacteria are inured to Biaxin, etc. Whereas Joe Worker, ordinary guy who's avoided doctors for the most part, is easily and successfully treated if he gets a serious infection. Just goes to show, even within our normal lifespan, the bugs in our bodies can evolve quite quickly.
  • >Other researchers said the finding does not >have serious implications for agriculture.

    i like this quote...now lets wait a few years till some real hard data comes out (like doing some studies on all those ppl sucking on their soya milk )...till then its non genetically modified for me! (if only i could tell the difference)
  • Some of these are raised in the article. We live in interesting times!

    Odd that you say that. "May you live in interesting times" is an old (Chinese, I believe) curse.

    --

    Michael Chisari
    dominion@beyondtheweb.com
  • Ok here are the problems with this report.

    One studying a single clone is like studying a single human being and trying to derive that what that human goes through all humans will do. If you
    were to study me, you would assume that all humans
    are left handed, far-sighted, like Free Software,
    and are green eyed.

    So dolly is showing some age in her genes. It could be due to telomere damage that was not corrected by the cell during incubation, or it could be a sign that her genes are a statistical
    anomoly...

    The problem with reading too much into this report is that if her mother was 6 years old when the cloning was done, and Dolly is 3 years old then shouldnt the damage be that of a sheep that is a nine year old sheep if no telomere damage had been averted. (Or did I misread something)

  • Some things to think about:
    * India and Pakistan are fighting over Kashmir, a disputed territory. Both have nuclear cabability. And to make it more interesting, Kashmir adjoins China.
    * U.S. is currently engaged in military action in Serbia. Serbia has strong ties to Russia. Russia's president is not exactly the most sober person at all times. Russia's economy is less than that of most third world countries. Russia has the world's largest arsenal of Nuclear Weapons.
    * Russia and China share a border.
    * The Cox report describes a Chinese program to systematically aquire US Nuclear technology, by buying or spying.
    * Israel is believed to have a nuclear capability. The upcoming declaration of independance of the Palestinian state will not be a calming influence.
    * Missing Uranium and Plutonium from government labs from Russia and the U.S.

    --And that's just current nuclear issues. Want to talk biomedical, bioengeneering, genetics, trade, research, the economy?

    -AK
  • We already know how to reset the telomere clock. There is an enzyme called telomerase which has a direct effect on the length of those sequences. I would be surprised if one couldn't pretreat a cell to reset this part of the clock before using it in the cloning process. (But then the researchers were hoping the enzymes were in the embreyo to erase the DNA gene memory.)

    Here are some links for more information.

    --Karl

  • The author of the parent comment raises exactly the points taht the scientists in question are rasing and examining.

    Most of the other comments here are as uninformed as the source article. I heard an interview with the head of the department on Today this morniing (BBC Radio 4 for US readers) and yes, the correct figures are 6,3 and 9 years, NOT 6, 3 and 6.

    The bloke said (as memory serves) "this is one measure of cell age (out of many), and we don't know how important it is over many generatiosn, but in a single case it is not important BUT WORTH INVESTIGATING, and the test size is only one, but this is the point of a test case".

    The more I read news on the web the more I despair for anything even approaching accurate reporting.

    Tim
  • I wonder now what impact this will have on Richard Seed's infertility work...

    You have to be kidding. Dick Seed?
  • To quote White Zombie (and Blade Runner):

    "I am the Nexus One. I want more life fucker, I ain't done."
  • Sequential cloning would be like making a copy on a photocopying machine, and then putting the new copy into the machine and repeating the process. Eventually, the copies become illegible.

    I'd hate to see an illegible sheep....

  • 7x10^5? What does this refer to? The average human cell can divide 50 (+/-10) times before dying (undergoing apoptosis to be technical). Of course, cancers and various immortal cell lines can do much better than that. I wasn't aware that they had any limitation. Although if they do, I suppose it could be something as large as 7x10^5. However, even if the cell divided once an hour (a very fast cell), this would still be 80 years of division before death. I don't think we've had immortal eukaryotic cell lines for 80 years, but I could be wrong. Where did that number come from? This is not intended as flamebait. I'm just curious.
  • The only use NASA could have is getting people off
    the planet that hate the crowding. And not many of them either.

    Figure out how many people are born every day, then figure how many spaceships/starships you would need to build and launch every day to simply keep the population stable.

    One of Robert Heinlein's books (Expanded Univeses ?) covers this well.

    As someone once pointed out, if we do nothing about population, then mother nature will, and she won't be nice about it !

  • Not surprising, albeit unexpected (Score:4)

    by lar3ry ( 10905 ) on Thursday May 27, 1999 @03:12AM (#1877768)
    This seems to reinforce the idea that there are "time bombs" in cells that cause the aging/death process. It may also be possible to extrapolate that something in the genetic material has "programmed" the apparent age.

    Some things to ponder:
    • If Dolly is three now, and appears to be six; in three years, will she appear to be nine, or twelve? In other words, is the aging process exponential?
    • New experiment: Save Dolly's genetic material, and use Dolly to clone another sheep, and check the genetic material in three years.
      What "apparent" age will the Dolly^2 have? Can we do any comparisons between Dolly, the original donor, and Dolly's clone? Is a clone of a clone even feasible?

    Some of these are raised in the article. We live in interesting times!

    --
  • AFAIK, she doesn't 'appear' older; i.e., her cells have less telomerase, but she doesn't outright show any aging differences.
  • Progress towards understanding telomeres and eventual production of artificial telomerase may help cure some causes of aging. However, most (or at least much) aging occurs not because of cells which normally divide ceasing their division, but because of cells which *don't* normally divide (brain cells, and IIRC bone marrow, for example) wearing out, completely independent of telomeres. So, immortality certainly won't be eliminated in one fell swoop -- but this is good progress towards extending the average lifespan by perhaps a few decades.

    To *cure* aging, we'll probably have to find a way to repair or replace cells which wear out, on a case-by-case basis. This could be anything from low-level repair via nanotech, to body-swapping (brain included) every half-century.

    -spc
  • Clone the clone, then clone that clone, then clone that clone, etc...

    If it stops working at some point we are missing a key element. If it doesn't stop working then we know that something about the enviroment of the host egg is resetting the genetic component of the aging process.

    By the way, the Tolomere theory is just one theory of aging. The fact that Dolly's tolomeres were shorter than average for a sheep her physical age does not neccessary lead to the conclusion that she is in some way prematurely aged.

    -josh

  • Not completely Off-Topic (Score:3)

    by jabber ( 13196 ) on Thursday May 27, 1999 @08:34AM (#1877773) Homepage
    I just thought I'd add this to the gene blender.

    Heard on the radio this morning, that the 6 billionth human is expected to be born in mid October. That's an awful lot of people on one mudball.

    Now, with Dolly, or Polly, or however many clones we make - giving us a shot at immortality in the long run, how will we do this responsibly?

    It only took a dozen years since we crossed the 5 billion population threshold to make another billion the old-fashioned way.
    Most of the earth's population is living in poor conditions.
    Buckminster Fuller proposed that the earth can easily support 10 billion people at luxurious quality of life, if we're responsible about it.
    We're not responsible.

    With cloning of humans a not-too-distant possibilty (humor me) and the natural population increase rate itself increasing; I hope NASA is doing it's job.

    -- It's all for nothing, unless we go to the stars.
  • Given current rates, we'll level off at about 12 billion around 2050....Gene therapy to counter aging won't have much of an impact, as it'll probably be expensive & difficult....it'll be just the elete of our society that will have this treatment....

    (and since growth is always exponential, mars, if compeletely terraformed, would only hold us over for a decade or 2)
  • I've seen some plants that have been cloned & recloned too often.....you can tell just by looking at them that something isn't quite right...there's errors in it's branching pattern, missing leaves, the works....

    Damn dyslexic RNA.....
  • Well, we know how to do system-wide gene modification, right? Theoretically, you should be able to add more headers to the DNA strands....

    Remember though, that cloning doesn't copy memories...so unless you have a CNS transplant, you'll just have a younger identical twin...

    That is, of course, assuming that life is "simply" a chemical function...

  • Not Necessarially Significant (Score:4)

    by Royster ( 16042 ) on Thursday May 27, 1999 @04:28AM (#1877777) Homepage
    The article [nytimes.com] that I read in the NY Times had some countervailing opinion. The size of the decrease is at the limits of the resolution of the measuring technique. We also don't know enough about natural variation in the size of telomeres to tell if the decrease is stastically significant.
  • Our "defense" against the killer bug is natural selection; if you survive it you pass on your genes and your offspring are more likely to survive.

    If our lifespans are lengthened but not our reproductive ones (i.e. we live 200 years but women can't have kids after ~50) then the bug doesn't really have much more time in it's arms race against us. If our reproductive age is lengthened as well, your right they would have a lot more time to evolve.

    Natural selection doesn't necessarily push microbes to be killers, though; the worst form of Ebola virus kills its victims so quickly that they have very little time to spread the virus to others. This kills the virus too, so there is some selection away from the most virulent strains.

    I think the most danger is a fluke cross-over from another species (like Ebola and HIV seem to be), then it wouldn't matter how long we were living. Just some thoughts to cheer your day . . . :)
  • We have cells in our lab that were harvested from a lady named Helen ~30 years ago(Hela cells) and they are still alive and kicking while Helen is not. This cells are very screwed up(>90 chromasomes) and they have active telmerase.
    I believe her name was actually Henrietta Lacks. Reader's Digest had a story about her some years ago. Her cells were widely used in cancer research and were known for "contaminating" other cell cultures, so that researchers who thought they were testing treatments on multiple cell cultures found that they were actually testing only HeLa cultures.
  • My big concern, is that we'll have 200, or 8000 year old goats and great^20 grandmama's running around(well moseying perhaps), and that's a DAMN long time as far as bacteria & virii are concerned.
    A hell of a lot of adaptation could occur in 200 years in a human host with non-changing genetic material. If we suddenly have arbitrarily long lifespans, will they adapt in amazing new ways to our code? Will these super-adapted virii be able to infect all humans, or will they adapt to a specific host?

    Kinda scary to me...
    --
  • Evolution doesn't try to perfect nature - it's blind, just surviving individuals tending to propagate more of the genes that resulted in survivability traits. There's no reason life should have provided such a mechanism - evolution "wants" to propagate only genes, not animals.
  • Don't forget that Dolly's short telomeres were completely expected, which is a good sign - it's further proof that telomeres are intimately related to aging. Given the exponential rise in genetic knowledge, anyone under 30 today can reasonably expect to live forever, reset to the 'default' physical age of 25, even if they've aged beyond that in the meantime.
    Of course, since dying itself is simply an evolved cellular-level defence against cancer, let's hope cancer is solved along the way.... (and before anyone answers the obvious point raised here, remember that evolution favours individual genes, not individual animals.)
  • I do not know whether this is related to what is happening to Dolly, but Seymour Benzer's lab [caltech.edu] at Caltech have found a gene (the Methuselah gene!) which increases the life-span of drosophila from 60 to 100 days.

    See also:
    http://www.newscientist.com/ns/9 81107/nshorts.html [newscientist.com] for a short note about the paper published in Science [sciencemag.org] (Search for Benzer, free registration needed to read the abstract).

    There is also a fantastic article on Seymour Benzer in the April 5 issue of the New Yorker.

  • Interesting point. But wouldn't it just be like having offspring when one is older in life. If someone sired offspring when they were 70 would their offspring have an older "genetic age"? I don't think so. The only problem that I can see is that Dolly may reach an age where she is too old to have offspring- three years earlier!

    At least for egg this isn't the case. The eggs are produced during fetal development and meiosis is halted just before the first division. They stay this way until ovulation when the cells divide and ovulate. That's why older women have a greater chance of birth defects, their eggs have been around longer and have a greater chance of being damaged.

    For sperm, I'm not sure what the development is like, but I suspect that it involves some type of way to prevent/reverse the degradation of the telomeres.

  • Just like Blade Runner (Score:3)

    by zagmar ( 20261 ) on Thursday May 27, 1999 @05:19AM (#1877785)
    You know, with short replicant lifespans.

  • 'Lectric Sheep (Score:3)

    by Dan Crash ( 22904 ) on Thursday May 27, 1999 @08:08AM (#1877786) Journal
    First it was the robotic fish [cnn.com], built in Japan, that could only be discerned from a real fish by a careful examination of its eyes. Now it is the premature aging ("four year lifespan"?) of replicant sheep.

    Certainly no one thought Philip K. Dick's novel was meant to be an accurate predictor of the future, and yet it's becoming more and more like the Bible of the 21st century. The real question is: Were the images of Dick (and Ridley Scott) accurate predictions of the future, or did those images play some role in creating the reality they predicted?

    It seems to me that if we grant the idea that images of the future tend to construct the future, then we've got a pretty nasty road ahead. I can think of a lot more dystopian sci-fi images than hopeful, positive ones.

  • There was an episode of Star Trek:TNG about this subject more or less. They visit a planet without sexual relations, and lots of identical people. They try to steal DNA from Riker and I think the Doctor to get an influx of DNA w/out telomerase degradation because cloning clones isn't working too well. Picard solves this by giving them a bunch of irish refugees and multiply with polygamy being the key. It was rather amusing to see Star Trek get something right for a change.
  • Well the computing solution would be to switch from using checksums to spot bad cells as it seems to do now and start using hamming coded DNA.

    That might take a few technology advances yet
  • You would be immortal only from a 'dying of old age' standpoint. I'm sure many things would still prove fatal. Anyone who had decided that they've had enough could still suicide. You would not be invulnerable.
  • Also the possibility of colonies underwater.
  • Simple, separate the carbon and the oxygen... now we can breathe... Then, combine some of the oxygen with hydrogen, now we have water. The carbon can be used to make diamonds(for tools) and the energy from the fission/fusion can be used to provide electricity to power the first colonies on Mars.

    Some people call me a dreamer, I call myself a thinker. (i'm not really a do-er)
  • As opposed to all those daily reminders of man's fallibility, which are merely annoying?
    --
  • This is interesting ... I wonder what 'age' Dolly will be at 6. Is this accelerated aging or 'catchup' aging?

    If genetics is anything like programming (grin), how do you reset the counters? Is it the ultimate one way hash algorythm?

  • living forever is almost as horrible a curse as knowing the future. Scarcity creates value. If your Time was no longer limited, it's value would move to zero and you would end up trying to suicide, which you couldn't do b/c you're immortal.

    My favorite immortal was from The HHGTTG series whose expressed immortal goal was the insult every living thing. Those are the kinds of things you'd have to do to fill up forever.

    The trick is to make something seem like forever while keeping it finite, and oh what a trick it is.

  • I was just about to quote Eldon Tyrell's line from Blade Runner:

    "The light that burns twice as bright burns half as long, and you have burned so very brightly."

    It sums it up very effectively.
  • I dunno. I'm halfway through the artice. I don't think this is such a bad thing. A nice reminder that humankind is fallable.

    Dirk
  • I had heard something similar recently, but IIRC the number of divisions was somewhere closer to 50 or 100 than 10^6. I could most certainly be wrong, though.
  • ....Immortality doesnt scare me, just if people keep there up this insanity they call living. that scares me.

    ever note that most of the genral media gives little or no attention to immortality research? hell, the last star trek moivie tryed to explane why immortality hasnt happen was just sorry. im starting to think that most people would rather die then live, forever.

    anyone have an ideas one why the commen WoMan, doesnt give a damn about immortality?

    nmarshall
    #include "standard_disclaimer.h"
    R.U. SIRIUS: THE ONLY POSSIBLE RESPONSE
  • ...yes you are right, the planet couldnt take it.
    but if you live FOREVER why not just take a trip to someother star? ie the problem of dieing could be fixed, after it is lets look for more! (problems to fix) anyway how meaningful is your or my life when we dont get to see but a little of Universe? i what to go crusing.. and look for some hot space chicks to fsck....

    nmarshall
    #include "standard_disclaimer.h"
    R.U. SIRIUS: THE ONLY POSSIBLE RESPONSE
  • I'm no astronomer, but what research I've done on Mars leads me to one conclusion. Mars just doesn't have enough resources to support very many humans. Unless there is hidden water somewhere (the ice caps are mostly C02), water is going to be really scarce.

    Maybe Mars can support, say, Los Angeles. If humans are in such a bind that population is growing too fast and there's no space on Earth, Mars isn't going to save us.

    While cloning and genetic engineering are very interesting, I don't think the human race is ready for it. We're just not responsible enough. See the movie Gattaca for a good explanation of why.
  • Evidence has been mounting that a cell's lifespan has a genetic basis. It's not, in otherwords, that cells suffer damage until they eventually 'give out'. Rather, some cells have a genetic cron|kill function.

    Now the trick is going to be to figure out how to reset the function.

    Immortality, anyone?
  • ....a rubber biscquit, of course
  • Interesting statement but slightly off base.
    "Of course, since dying itself is simply an evolved cellular-level defence against cancer, let's hope cancer is solved along the
    way.... (and before anyone answers the obvious point raised here, remember that evolution favours individual genes, not
    individual animals.)"

    I like to think of cancer as god's way of telling us that we have lived too long. Cancer is actually a fairly well understood process but the players are not. Let me explain. Cancer is the result of a disregulation of genes involved in cell growth and differentiation and can be broken down into two groups. The first group are cancers such as breast cancer which have genes screwed up that regulate growth of an individual cell which allows that cell to grow outside of the normal regulation. The second type of cancer are cancers such as non Hodgins lymphoma which prevent a cell from comiting suicide (apoptosis) when they are supposed to. I am sure that some could be a mixture of both.
    With this said, for a cell to become malignant and result in the death of the organism, many genes must get genetically hit or mutated. The mutation can be in the coding region of the protein or in the promoter or both. So cancer that kills is actually an accumulation of mutations rather then just one mutation. The genes that must be mutated are termed oncogenes and thier normal couterparts are call proto oncogenes. Here in lies the problem. Who are the oncogenes? We know of many but not all. Also, what mutation is important? Does the promoter region need to be hit or does the protein need to be hit? Our current understanding of promoter regions is very primative to say the least and it may be decades before we understand them more fully. Short range enhancer regions(on switches) are relatively easy to find but enhacers located far away are dificult to identify and enhancers within introns(non coding region of genes) go virtually unexplored.
    Over time, we all get mutations in our genes and that is unavoidable. If you use that DNA for cloning then the mutations will accumulate even more till cancer is unavoidable. A good example of this is pediatric cancers. These individuals are ussually born with only one good copy of a key gene and if mutations occur in the only good copy then cancer is sure to occur. This is how the Retenoblastoma gene was found and Wilms tumor antigen as well.
    So in a nut shell, Cancer is solvable only if you know what genes are screwed up but to determine that the genome needs to looked at. And that is no small task

    Regards
    Peter

  • Dolly and Telomeres (Score:4)

    by pedi ( 43054 ) on Thursday May 27, 1999 @07:36AM (#1877804)
    What is happening to Dolly's clones is a predictable event and one which did not surprise me at all. It simply proves a point.
    Eucaryotes(aka multicellular life forms) have linear Chromosomes as opposed to prokaryotes(bacteria) which have circular chromosomes. Each time a linear chromasome replicates thru cell division, it losses some of its ends. This is called degenerate replication. An enzyme with an RNA core (used as a template) is used by the cell to replace the bases that can not be replicated and it is called Telomerase. The strech of DNA that is shortening is called the Telemere. Normally, telomerase is NOT active in cells other than in very early life(before the 2nd trimester). Although it has been found in some cells in the adult. Those cells are believed to be the pluripotent stem cells(capable of forming just about any cell in the body) and CANCER cells. If a cell wants to live forever, telomerase will have to reawaken and repair its ends if it does not, the belief in the scientific community is that the cell will undergo "Programmed death" (aka apoptosis) when the telemeres on the ends of the chromosome gets to short. An example of this principle can be seen in the disease ATAXIA TELANGIESIA (AT). These poor souls are born with abherently short telomeres and by the age of 18, the individuals resemble a 70 year old.
    With that said, the DNA that was used for Dolly's clones was obtained from the breast of Dolly and the cells were fully differentiated and thus had already undergone significant shortening of the chromosome before the DNA was harvested. One would expect several things to happen. 1) DNA will age faster due to telemeric shortening and 2) DNA will have acumulated mutations from Dolly's life as well as from its own life and thus will have a higher disposition for cancer. I define cancer as the acuumulation of mutations that allows for genes to be disregulated and thus cells live when they should die. We have cells in our lab that were harvested from a lady named Helen ~30 years ago(Hela cells) and they are still alive and kicking while Helen is not. This cells are very screwed up(>90 chromasomes) and they have active telmerase.
  • I think that living forever is HIGHLY overrated. Dying and disease is a natural process that keeps the planet from becoming overpopulated. What if nobody died of old age? I shutter to think of a world like that.

  • Cloning promises many good things....
    All I worry is that the rich people of this world, that everybody hates, clone themselves!!!!!

    Think of it...
    A troop of Trumps...
    a swarm of Simmons (Richard! ack!)
    We must make laws against this abuse of science, everyone!!
  • It's a copy. Every time you make a copy the quality degrades. This is what happens when you to make a copy using analog connections. Somehow I blame this on the RIAA. Perhaps Dolly should have been placed on a CD then digitally remastered?
  • " I mean, for one thing, they didn't need to get any sort of large, obvious genetic sample, they could have simply picked up bits of dead skin that the away team left behind."


    Well, PCR is quite error-prone, so it would be better to have a large sample of real DNA. Of course, that's assuming that this advanced civilization had nothing better than crude 1990s PCR techniques for DNA amplification.

  • LOL.

    My thoughts exactly -- you beat me to it. I'm sure it's some kind of cosmic contingency against bio-piracy.

    I wonder what the fines are if you're caught? ;-)

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