
Congress Revives Ban on Altering the DNA of Human Embryos Used for Pregnancies - headalgorithm
https://www.scientificamerican.com/article/congress-revives-ban-on-altering-the-dna-of-human-embryos-used-for-pregnancies/
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adrianN
How reliable are techniques for fixing single-locus mutations in mammal
zygotes? I heard that CRISPR is not all that reliable and the risk of
introducing unwanted changes is fairly high. Does anybody have numbers about
how many embryos you would have to go through on average until you get one
with exactly the alteration that you wanted?

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Symmetry
If you're looking for offspring without some particular mutation you're much
better of with embryo selection rather than trying to use CRISPR. It's only
when you have some specific trait not present in the parents that you'd even
want to consider it, really. Well, if you've got a problem on the y-chromosome
or the mitochondria then you have a good medical reason but there just isn't
that much on the y-chromosome and the three-parent embryo thing in the article
is a good solution for mitochondrial DNA problems.

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derefr
What about some specific trait present in both parents, that will get worse in
the child if both parents have it, because it’s a phenotype influenced by the
number of copies of a gene the parents each have, and the gene is dominant?
Cystic fibrosis, for example. Be nice to just slice all the copies out and
start fresh, so that the child isn’t even a carrier.

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Symmetry
I'm confused here, I'd always thought that Cystic Fibrosis was a classic
Mendelian recessive and a quick look at Wikipedia suggests that's correct. If
you want to get rid of an autosomal recessive gene through embryo selection
just make a few blastocysts and only implant one that doesn't carry any copies
of the allele you don't like.

If you do have a gene with a number of copies on each chromosome, like the one
for amylase say, the number of copies of one type or another don't generally
have enough of an effect to get too worked up over it?

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hanniabu
While I understand the concerns with this, I highly doubt our government does
(they still don't understand the internet). I'm a believer that this ban is
centered around religion and the fear that if man can "create" then it takes
away from religion and a God creating man.

