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Comment by m_mueller | Hacker News Reader

Isn't that currently just a matter of legality and cost? You can already test for trisomy syndromes by sequencing a bit of the mother's blood around week 10 and isolating the embryo's chromosomes statistically - that probably takes a very fault tolerant kind of sequencing, but throw in an order of magnitude more money or a couple more years of cost reductions and you're there.

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Right, but at ten weeks, all you can do is abort, which means it's only practical to screen for a few different genetic flaws this way, particularly if you expect some of them to be bad Mendelian inheritance and not some kind of rare structural flaw. Suppose you want to screen out four recessive traits and each one is inherited with probability 1/4, the probability of rolling a good combination is (3/4)^4 = ~30%. If you want to screen out ten such genes, the probability of a good combination drops to ~5%. With embryo selection, you can perform all the trials in parallel instead of sequentially at ten weeks per trial.

You're still flushing all the other embryos down the drain. It doesn't seem as awful as lots of other shit that happens every day, but it's certainly sketchy enough that I wouldn't do it. Humans are not livestock.

Can you define what’s the moral difference against trisomy prescreeners? Or are you against these too? Honest question btw.

I'm not 100% comfortable with the trisomy thing, but I understand why people do it. The "moral difference" is primarily one of scale. Choosing to abort or not, in one particular case, is a human decision. That's even true of abortions motivated by "less moral" factors like economics or convenience. Those are still human decisions.

Deliberately aborting 99 out of 100 or 999 out of 1000 or whatever, that's not how humans interact with each other. That's the sort of decision-making I reserve for cattle or other livestock. (Although we wouldn't make much money if we were so Procrustean in our evaluation...) In that sphere, it's considered immoral by lots of perfectly sane people.

I'm not saying that this practice will never be normalized and accepted by most people. I am saying that if researchers try a little harder and develop methods with the same results but less abortion, the world will be a better place.

Good point about scale. Tbh. I doubt that more than an 1/10 ratio is going to be feasible due to limits given from female biology. If people start doing that, something like CRISPR will soon be employed to fix such issues directly - if the west doesn’t allow it, people will simply travel to a country that will. For families with severe disorders, the cost of doing so will be much lower than to just take the chances with nature, so I think there’s going to be sort of a price balance for each illness. The main risk IMO is a Gattaca-style dystopia.

Not all sunshine & roses. Here's a dark factoid for you- my memory is a bit fuzzy on when you chose mother's blood vs amniotic fluid sample for the test, but at the time I learned about all this, the odds of taking the amniotic fluid sample causing spontaneous abortion, were higher than the odds of the fetus having the more common trisomy conditions. For any particular fetus, the test was more risky than the disease.

It doesn't follow that the test is useless: you're still minimizing the number of people with genetic abnormalities, even if you're causing some spontaneous abortions along the way.

Yes, I don't claim the test is useless. But it was an unexpected moral quandary, as my spouse and I are not strict believers in either pro-choice or pro-life.

That depends on how you weigh a spontaneous abortion against having a child that will never be independent.

The test I’m referring to only uses blood from the mother, thus it should be risk free.

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