Slashdot Mirror


Scientists Silence Extra Chromosome In Down Syndrome Cells

An anonymous reader writes "Scientists have silenced the extra copy of a chromosome that causes Down syndrome in laboratory stem cells, offering the first evidence that it may be possible to correct the genes responsible for the disorder. The discovery provides the first evidence that the underlying genetic defect responsible for Down syndrome can be suppressed in cells in culture."

25 of 230 comments (clear)

  1. Comment removed by account_deleted · · Score: 5, Insightful

    Comment removed based on user account deletion

  2. Practicality? by APE992 · · Score: 3, Interesting

    Assuming we could silence the extra chromosome in an entire human being what sort of results would we see? I'm curious to see the changes that would occur over weeks if not years. Could it reverse the neurological issues?

    1. Re:Practicality? by quenda · · Score: 5, Funny

      Could it reverse the neurological issues?

      Hard to say until the animal trials are complete. So far Algernon is doing well.

    2. Re:Practicality? by MightyMartian · · Score: 5, Insightful

      Maybe some aspects of Downs could be reversed, but as many of the neurological and physiological aspects of the disorder are doubtless developmental, I can't imagine any substantial changes to a person already with the syndrome. The greatest hope, I imagine, is in utero treatment which would prevent the developmental aspects of Downs Syndrome from happening at all.

      --
      The world's burning. Moped Jesus spotted on I50. Details at 11.
    3. Re:Practicality? by Richard+Dick+Head · · Score: 5, Interesting

      Well, if you'll put on your cyncial hat, the in-utero treatment you wish for already exists:

      plannedparenthood.com

      Some of these treatments coming out really make me worry for the future. Random mutations make their way in a consistent fashion into the human gene pool, and stuff like this prevents them from being filtered out. As cool as this would be *now*, given enough generations these mutations will disburse (ever wonder why so many people have blue eyes?) and eventually the entire human race becomes diseased and enslaved to these treatments.

      I mean, come on...if you subsidize something, you get more of it. if it isn't strong and healthy, throw it out and pump out a new one. Its not like we're suffering a worldwide shortage of semen at the moment!

      And before I hear one more sob story about how great "X" family member was and how they had the disease, let me remind you that our tax dollars are subsidizing the situation (many many times more than a regular child for special needs care)...yes, people feel the warm fuzzies when they encounter a less capable people who deals with their situation in a positive fashion, but that doesn't make it right, or proper.

      I don't know, am I just too cynical? I think at a certain point you're gonna get a test result back and either you do the right thing, or you elect to have a human pet that is a drain on society (but nice for you). I think that stinks. Look around, we're already busting at the seams because there is less and less meaningful work for someone who falls below a certain point on the bell curve, and its getting worse as time goes on.

    4. Re:Practicality? by Dexter+Herbivore · · Score: 3, Funny

      I'll make sure to get him some flowers and a get well soon card then.

    5. Re:Practicality? by ShanghaiBill · · Score: 5, Interesting

      Well, if you'll put on your cyncial hat, the in-utero treatment you wish for already exists:
      plannedparenthood.com

      In America, about 90% of diagnosed DS fetuses are aborted. That is an interesting percentage, since polls indicate that more that 20% of Americans think abortion should be illegal under all circumstances. At least half of those people are apparently hypocrites, willing to make an exception for their own convenience.

      Citations:
      http://www.gallup.com/poll/1576/abortion.aspx
      https://en.wikipedia.org/wiki/Down_syndrome#Abortion_rates

    6. Re:Practicality? by Zembar · · Score: 4, Interesting

      That's not necessarily true. What if those 20% were all men, for instance?

    7. Re:Practicality? by ShanghaiBill · · Score: 3, Interesting

      That's not necessarily true. What if those 20% were all men, for instance?

      Polls have found that gender makes little difference in support/opposition to abortion. Support is only slightly stronger among women, and even then, only among educated women. If you had bothered to read the citations provided, you would already know this.

      It is also unlikely that most decisions to abort a DS fetus are made unilaterally by only the mother.

    8. Re:Practicality? by Anonymous Coward · · Score: 3, Insightful

      Are screening tests that pick up DS done for all pregnancies? If they aren't then maybe the discrepancy you see is because the people who think abortion is illegal are more likely to not do the DS screening tests during pregnancy.

    9. Re:Practicality? by An+dochasac · · Score: 4, Insightful

      Well, if you'll put on your cyncial hat, the in-utero treatment you wish for already exists: plannedparenthood.com

      In America, about 90% of diagnosed DS fetuses are aborted. That is an interesting percentage, since polls indicate that more that 20% of Americans think abortion should be illegal under all circumstances.

      Since we're talking statistics, amniocentesis, the invasive test for Down Syndrome, has a 0.75% chance of ending the pregnancy so we opted for a lower risk combination of an ultrasound scan and blood test. The results (along with our age and other factors) gave a 1 in 40 (2.5%) chance of a baby with Down Syndrome. But the nurse who read the results to us didn't say once chance in 40 and she didn't say 2.5% chance. She said 40% chance! (Is mathematic literacy a medical training requirement.) Fortunately we did the tests merely to inform ourselves of what special preparation we might need to make. Abortion for eugenic purposes is not legal here in Ireland as it is in the US. Unfortunately this same nurse trained in Boston. Heaven only knows how many pregnancies were ended based on this. We're thankful for a healthy little boy who doesn't have Down Syndrome but we may all owe a debt of gratitude to people with Down Syndrome. Studying the characteristics of this syndrome may help us understand Alzheimers and studying the fact that cancer is much rarer in people Down Syndrome may help us understand and cure this terrible disease.

      The take no prisoners battle between the anti-life and anti-choice people have left us in a state of anti-science, anti-compassion and anti-love.

    10. Re:Practicality? by gumpish · · Score: 3, Insightful

      Yes I deliberately used a term that was just as charged as the common "anti-choice" term that you've heard so much on news media and in pop political-culture ... The phrase "Pro Choice" is not descriptive. (Pro choice about what? iPod vs Android, Republican vs Democrat?, Beans vs Carrots?)

      This smacks of intellectual dishonesty. When you hear a politician describe themselves as "pro-choice" do you actually find yourself confused as to what issue they're referring?

      As to the question of descriptiveness, "pro-life" is decidedly less descriptive than "pro-choice". People who identify as pro-choice support the idea that women should be able to choose whether or not to terminate their pregnancy. People who identify as pro-life don't oppose ALL deaths. (In fact I suspect the majority of them support capital punishment, at least here in the U.S.) They are specifically opposed to abortion so their position is more accurately described as anti-abortion. "Anti-choice" is lacking since that term could be used to describe someone who supported mandatory abortions. (But then I personally haven't heard that term "on news media and in pop political-culture".)

      Nor does the phrase "Pro Choice" accurately describe the plight of women in places where abortion is not only permissible, it is mandatory.

      Who exactly is claiming that regions with mandatory abortions are "pro-choice"?

  3. Tricky to translate to primetime by Blugenes · · Score: 4, Informative

    This sounds neat but will be very difficult to translate into practical applications. First there would likely be an extra chromosome in every cell in the body, so unless you can engineer a means to silence the additional chromosome in every cell of the body then this is either a partial or nonfunctional solution. Second there are means of having a Down Syndrome phenotype that involves an imbalanced translocation in which you effectively have two chromosome 21s attached to each other, this therapy would probably not work for those patients. And finally the XIST gene is talking about shutting down an entire chromosome, while this might work in a petri dish or lab animal this will be a therapy specifically designed to treat children. Will they have to be screened prior to conception? Will there have to be treatment in utero to make it effective? I commend the researchers on the effort but this whets the whistle, and given the paucity of research funding lately perhaps the main point of the article is to drum up support for more grants instead of relay practical discoveries.

  4. The Ethical Implications are Staggering by zbobet2012 · · Score: 3, Interesting

    Oh god, the ethics debates on this one will be fantastic. What if we can reverse Downs Syndrome in full grown adults. By modern legal definitions those with it are not competent, but could we ethically force them to take the "cure" if they don't want to? What if a mother does not want to have it "fixed" in her unborn child, is she a competent parent?

    1. Re:The Ethical Implications are Staggering by vikingpower · · Score: 5, Interesting

      I don't know if you can emit such a blanket statement as "...by modern legal definitions those with it are not competent..." There is debate about this, and at least here in Europe, those with it are more and more living their own lives. The 17-year old daughter of a colleague has it - and she is not only learning the trade of a baker: she is preparing to live alone, in an apartment in the middle of the city. She already manages her own money and her own relationship with various administrative bodies. With her father's support, but still - this would have been unthinkable even ten years ago.

      --
      Religous speak to God. Insane are spoken to by God. When all shut up, one can finally hear Shostakovich in peace
    2. Re:The Ethical Implications are Staggering by mjwx · · Score: 5, Informative

      There is debate about this, and at least here in Europe, those with it are more and more living their own lives. The 17-year old daughter of a colleague has it - and she is not only learning the trade of a baker: she is preparing to live alone, in an apartment in the middle of the city. She already manages her own money and her own relationship with various administrative bodies. With her father's support, but still - this would have been unthinkable even ten years ago.

      This is also happening in Australia.

      They are teaching people with disabilities to live on their own, not just in halfway houses but on their own, managing most of their own affairs. Some are down to 1 hour a week with social workers, stuff the cant take care of on their own they know to save for that time.

      A far cry from 40 years ago where kids with down syndrome were sterilised.

      --
      Calling someone a "hater" only means you can not rationally rebut their argument.
    3. Re:The Ethical Implications are Staggering by DigiShaman · · Score: 4, Interesting

      I'm not a geneticists.

      Of all the adults out there with Downs Syndrome, how many of them go on to get married and have children? Of those that have children, what is the likelihood of this abnormality being passed down the family tree? I'm not disputing their choice to procreate. I am however concerned that suppressing the extra chromosome will lead to healthy adults (which is very good), but also have normal procreating life and thus pass it down to the next generation (which is bad). Do we to to encourage adding severe genetic abnormalities to future generations if all were doing is suppressing them rather then removing/correcting said genes? For the sake of the human race, this requires serious consideration.

      --
      Life is not for the lazy.
    4. Re:The Ethical Implications are Staggering by Anonymous Coward · · Score: 4, Informative
      I actually had thought Down syndrome was not heritable and went to look for a reference... only to find that it is:

      Males with Down syndrome usually cannot father children, while females demonstrate significantly lower rates of conception relative to unaffected individuals.[43] Women with DS are less fertile and often have difficulties with miscarriage, premature birth, and difficult labor. Without preimplantation genetic diagnosis, approximately half of the offspring of someone with Down syndrome also have the syndrome themselves.[43]

      from Wikipedia ([43] is this research paper).

  5. Re:Even if it does... by tloh · · Score: 4, Insightful

    The point? How about early intervention? Trisomy 21 is easily detected via procedures such as amniocentesis which are trivial to perform today. If you can catch the condition early, much of the developmental abnormalities that would have progressed unchecked in a normal Downs Syndrome baby could be nipped in the bud during fetal development. I'm not sufficiently experienced in this area to make dramatic claims. But I would venture a guess the earlier you can address the problem in the womb, the less severe the symptoms would be in an affected individual.

    --
    Stay sentient. Don't drink bad milk.
  6. Actually.... by Anonymous Coward · · Score: 5, Interesting

    It could also potentially help curb many of the plaque related neural issues (I think it was mentioned on slashdot years ago that Down syndrome had plaque buildup similiar to alzheimers.) Assuming this chromosome is in part responsible for that plaque buildup, it might allow more Down syndrome sufferers to continue functioning at their current level rather than degrading further in the future.

    Regardless, anything that moves forward the treatment of disease in the world is good research.

  7. Re:Even if it does... by swamp_ig · · Score: 4, Informative

    By the time you've had amniocentesis to diagnose the disorder, the damage is already done.

    Development has largely happened by the 12-14 weeks at which point amniocentesis is viable, from there on it's really just growing with a few bits of finishing off.

    Unfortunately the only 'cure' for downs is to terminate the pregnancy when it's detected. In fact a considerable percentage of affected pregnancies end in miscarriage anyhow.

  8. Re:Even if it does... by Anonymous Coward · · Score: 3, Insightful

    I take it that you've never had the pleasure of being around those with Down's. They are wonderful people and their brutal honesty is hilarious; they hold no punches when someone is in the wrong.
    Personally, I am against aborting them and FWIW I'm atheist.

  9. Re:Even if it does... by SuricouRaven · · Score: 3, Interesting

    And if fixing the laptop would cost more than buying a new one, throwing it in the trash is still the more sensible approach.

  10. Re:Even if it does... by Anonymous Coward · · Score: 5, Interesting

    (different AC here)
    I get the impression that GP has never gone through the process of trying to conceive, or the high emotions and huge decisions of pregnancy. This isn't 3D printing we're talking about. For many people it's not as simple as "scrap this one and start over." A couple's fertility is unpredictable, riddled with limitations and risks, and it's a lucky minority that conceives first time, every time.

    Imagine you're a couple trying to conceive. You thought you'd get pregnant easily, just when it fitted conveniently into your life schedule (everyone thinks that). You weren't young when you started, but not too old either - late twenties is more the norm than the exception these days. Anyway, it took longer than you thought. By now you've been trying to conceive for years. Maybe you've had a miscarriage or two. Doctors cant see what the problem is, as is often the case with reproductive medicine: Everything looks fine down there, but it just ain't happening. IVF is prohibitively expensive, and still offers no guarantees. At first your failure to conceive was an irritation, a disappointment. Now it's more than that. Time is ticking on and your body is screaming at you to have a baby nownownow, and there are reminders everywhere of the one thing you want but apparently can't have. It's starting to affect your happiness, your marriage, maybe even your mental health. This is not science fiction, this is a situation a lot of people find themselves in nowadays in western society.

    Finally, as you approach your mid-thirties you get pregnant. Your are ecstatic, delighted, happier than you've ever been. Then, the tests show Downs.

    If you abort and try again, it could take another 5 years to get pregnant again, if at all. Do you really want to be conceiving at 38 or 39, when the chances of Downs or some other, even more severe complication, will be even higher? Do you really want to be 40 and pregnant? Do you really want to be nudging 60 when your kid hits adolescence? What if you can't conceive ever again? What if this is your only chance? "Scrap it and try again" or "abort and adopt" may be viable options, but they do not by any means represent an obvious or easy choice for someone in that position.

    I'm not entirely opposed to abortion. I think it's a very personal choice, and a morally difficult issue. I don't believe a microscopic zygote is as much a human being as an adult or a newborn or a 25-week foetus, but I do realise that any hard line drawn between "cluster of cells" and "person" will be arbitrary and ultimately unsatisfactory.

    The point I'm drifting away from here is that even in cases where it is unwanted, a pregnancy is a very precious and special thing, and should not be discarded lightly. In cases where it is wanted, it is even harder to "scrap it and start over."

  11. Re:I approve by Russ1642 · · Score: 5, Funny

    When the admins find a story that applies directly to them they can't help but post it.