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Sequencing the Unborn

sciencehabit writes "What if you could read much of your child's medical future while it was still in the womb? Taking a major step toward that goal, one fraught with therapeutic potential and ethical questions, scientists have now accurately predicted almost the whole genome of an unborn child by sequencing DNA from the mother's blood and DNA from the father's saliva (abstract)."

27 of 146 comments (clear)

  1. Odd by taktoa · · Score: 2

    I don't see how this is possible, given that genetic recombination happens. Unless the parents are very genetically similar (ick), there should be billions of possibilities.

    1. Re:Odd by Anonymous Coward · · Score: 2, Informative

      I think this is the relevant part of the article: "In most cases, for a particular genetic sequence on a specific chromosome, the variants from each pair should be represented equally in the woman's blood. But in an expectant woman, whose child has received only one variant as part of its genetic inheritance, her blood will contain a little more of that variant because of the free-floating fetal DNA. If the mother's patterns of genetic variants, or haplotypes, are known, statistics allow researchers to conclude what variants she passed on to her offspring. In 2010, Lo showed that with both parents' haplotypes known, it would be possible to predict the child's genome from the DNA in an expectant mom's blood."

    2. Re:Odd by Anonymous Coward · · Score: 3, Informative

      I don't see how this is possible, given that genetic recombination happens. Unless the parents are very genetically similar (ick), there should be billions of possibilities.

      This problem is my area of research (didn't RTFA, just assuming this is how they did it). There is cell free fetal DNA circulating in mothers and the challenge is isolating enough of it for deep sequencing without contamination from mom. I'm assuming they are using dad's DNA to help 'choose' between competing reads to figure out which ones are mom and which ones are fetal in origin. A less sophisticated version of this approach has been used to test for TS21 (Down's syndrome).

    3. Re:Odd by interkin3tic · · Score: 4, Informative

      To summarize: it's not yet possible to isolate only embryonic DNA from the mothers' blood, so using the father and mother's DNA sequences, they can tell which sequences are from the mother and which one are from the embryo.

      Without the father's sequence, the confidence in the sequencing probably goes down, but is still possible.

  2. They made a movie about this... by Mark+Rawls · · Score: 2

    And it was called Gattaca.

    1. Re:They made a movie about this... by Jeng · · Score: 2

      Yes in Gattaca you could tell the genetics of your unborn child, but you could also do genetic engineering on the unborn child in Gattaca and it was that portion that had more to do with the plot.

      --
      Don't know something? Look it up. Still don't know? Then ask.
    2. Re:They made a movie about this... by QuasiSteve · · Score: 2

      I guess that depends on how you view the 'engineering'.

      No modifications were made to fertilized eggs, iirc.

      But let's say you have 8 fertilized eggs, but only the desire for 1 child - then isn't picking one of those 8 that meets your 'demands' tantamount to engineering?
      What if you don't pick any of the 8, and instead fertilize 8 more, and again, and again, until you hit the result you were hoping for?

      This is at the core of much of the debate on genetic engineering, in that some genetic modifications are simply shortcuts to what random mutations may otherwise cause. What's the difference if instead we let nature (or God for those so inclined) make the modifications for us and we just carefully pick them out from the plethora of other modifications, other than - likely - a whole lot of time?

    3. Re:They made a movie about this... by zill · · Score: 4, Informative
      Straight from the script:

      Now you appreciate I can only work with the raw material I have at my disposal but for a little extra...I could also attempt to insert sequences associated with enhanced mathematical or musical ability.

      Emphasis mine.

  3. Re:TFA's Scientist's take on Gattaca problem by CodeHxr · · Score: 4, Insightful

    The caveat to this is that "ethical" is opinionated and everyone's is different. Even if the laws of your area are completely aligned with exactly how you feel about the ethical implications, there will be other areas that have vastly different laws. Even within any given area, there will be people who think the law doesn't apply to them and take things into their own hands.

  4. Let me be the first one to say it: by blind+biker · · Score: 4, Insightful

    "Gattaca" wasn't fiction - it was an accurate prediction of a dystopian, fast-approaching and very real future.

    --
    "The agriculture ministry is not in charge of Gundam" - Japanese ministry official.
    1. Re:Let me be the first one to say it: by Eightbitgnosis · · Score: 2

      Would you not give your child vaccines because it's not fair to those children who do not receive them?

    2. Re:Let me be the first one to say it: by EvolutionInAction · · Score: 2

      It's nice to see somebody else who felt that way. It would suck for the transitional generation, it's true, but in general people were stronger, healthier and smarter. How is that bad?

    3. Re:Let me be the first one to say it: by mcmonkey · · Score: 2

      "Gattaca" wasn't fiction - it was an accurate prediction of a dystopian, fast-approaching and very real future.

      You misspelled "Idiocracy"

  5. Re:TFA's Scientist's take on Gattaca problem by Anonymous Coward · · Score: 3, Insightful

    Forget about traditional ethical concerns, the later in onset and more multi-factorial the disease, the less informative genetics and genomics is. Even if genetic loci can explain 10% of phenotypic variation in a given cardiovascular phenotype, who cares (aside from, perhaps, a poorly run insurance company)? Any number of biochemical markers of disease are MUCH more predictive than genotype for a host of such diseases. Your BMI, your random and fasting blood glucoses all predict your risk of T2DM MUCH more accurately than the sum of all genetic loci known to contribute to the disease.

  6. Eugenics by Ironchew · · Score: 5, Interesting

    What if you could read much of your child's medical future while it was still in the womb?

    The more worrying question here in the U.S. is, "What if your insurance company could decide your child's medical access while it was still in the womb, based on poorly-understood genetic risk factors and eugenics pseudoscience?"

  7. Re:TFA's Scientist's take on Gattaca problem by interkin3tic · · Score: 3, Interesting

    I disagree with you both. I find nothing ethically wrong with abortion or screening for diseases. How about we let parents decide whether it's ethical for them?

  8. Re:What about genomic testing before marriage/mati by OSU+ChemE · · Score: 2

    They took the blood from the mother after she was pregnant, when there was fetal DNA in her bloodstream and are essentially doing a 'process of elimination' among the fetus, mother, and father. So while you could do a pre-conception screen, and it may indicate probabilities for genetic disorders or diseases with a genetic component, it wouldn't be the same thing as in TFA.

  9. My WTF, explained by jfengel · · Score: 4, Informative

    What's decidedly unclear from the summary: they're sequencing fetal cells found in the mother's blood. It was separated from the mother's own blood cells with a nify trick using the father's DNA.

    So it allows them to sequence the baby's type without having to touch the infant itself. They're not making any "mother+father=baby" predictions before the baby is conceived, which would be impossible just from their ordinary (somatic) cells.

  10. Re:TFA's Scientist's take on Gattaca problem by spazdor · · Score: 2

    no, but the informative-ness of your medical history grows monotonically as you age.

    --
    DRM: Terminator crops for your mind!
  11. Re:TFA's Scientist's take on Gattaca problem by LordLimecat · · Score: 4, Insightful

    How about we let parents decide whether it's ethical for them?

    Thats begging the question: Its only OK to let the parents decide whats ethical, if your stance on abortion is correct. If it isnt, your argument would be akin to "why not let the parents decide if they want to abandon their newborn".

    Not trying to be flame/troll bait here (even tho I likely will be modded as such), but the entire argument from most prolifers is that the fetus is every bit as human as a newborn is. Unless you start off by assuming theyre wrong (again, begging the question), you cant just say "well, lets let the parents decide whether thats true"-- because we DONT take that stance with a baby post-birth.

  12. Re:TFA's Scientist's take on Gattaca problem by cayenne8 · · Score: 2

    The caveat to this is that "ethical" is opinionated and everyone's is different.

    For sure.

    I mean, I would nave absolutely NO problem with wanting to terminate the pregnancy if I found out the kid was going to be retarded, or crippled....anything that would keep it from starting out with a 'normal' childhood. In fact, I'd welcome it...I think many people might like this option, especially if you're a bit older having kids....which is happening more and more these days.

    Different strokes for different folks....I respect those who would have a different opinion on this...but that's mine.

    --
    Light travels faster than sound. This is why some people appear bright until you hear them speak.........
  13. Re:TFA's Scientist's take on Gattaca problem by Anonymous Coward · · Score: 3, Insightful

    Well, I just don't care for turning women into baby-making machines and telling them they don't control their own bodies. Freedom of an already born, thinking individual > life of an unborn human leeching off of a women. For me, anyway.

  14. so who decides? by Chirs · · Score: 2

    What about the people that terminate because it's a girl?

  15. Re:TFA's Scientist's take on Gattaca problem by interkin3tic · · Score: 4, Insightful

    Thats begging the question

    Stop right there. No it's not. I'll let you ask your question anyway, but it's going to be a strawman argument.

    your argument would be akin to "why not let the parents decide if they want to abandon their newborn".

    Called it! That's a strawman. We're not talking about a newborn, we're talking about an embryo. Everyone agrees that a newborn has rights, there is no consensus as to whether an embryo does. Furthermore, a newborn is not an obligate dependent on one specific person, newborns can be dropped off at any safe baby haven or given up for adoption. There's no similar alternative for pregnant women.

    My point here is that this is a totally separate issue from abandoning a newborn.

    Answering your point, no, I don't think letting the parents decide whether abortion is right or not for them is only ethical if we assume life does not begin at conception. In most countries, most ethical decisions are left up to the individual. There's no law that says I can't cheat on my wife, it's up to me to decide if I think that's ethical or want to do that. Lacking a law against adultery is not an unethical situation, it simply leaves the responsibility up to the individual.

    Legalizing abortion doesn't endorse abortion, it only leaves the ethical question up to the people who deserve to make the choice: the parents.

  16. Re:TFA's Scientist's take on Gattaca problem by LordLimecat · · Score: 2

    Well, I just don't care for turning women into baby-making machines and telling them they don't control their own bodies.

    And that, friends, is what we call a false dichotomy.

    Im fairly certain that there are a plethora of choices that dont involve an abortion-- even if you dont count the "day-after" pill.

  17. Re:TFA's Scientist's take on Gattaca problem by jrroche · · Score: 2

    Im fairly certain that there are a plethora of choices that dont involve an abortion-- even if you dont count the "day-after" pill.

    What? There are two choices. The woman carries the child to term or she doesn't. If a woman is pregnant, the only choice other than abortion is to carry the child to term, unless you count an unintended miscarriage as a choice, which, if unintended, it could not be. ...wait, are you thinking of that DS9 episode where Bashir transplants Keiko's baby into Kira? You know that's not real, right?

  18. Re:Wait, what? by shellbeach · · Score: 2

    This problem is my area of research (didn't RTFA, just assuming this is how they did it).

    Am I the only one who thinks this is kind of amusing?

    Amusing and also kinda sad. At the least the poster deduced things correctly, I guess ...

    Wonder if this is the first time someone's discovered they've been scooped by reading /.??