1kanzure2yIt really depends on your technique. If you are doing CRISPR microinjection
(which is very simple, and you should probably not do, because there are other
better techniques) then there will likely be off-target mutations. However, in
other techniques, you can do quality control, screening, and sequencing before
the cells divide or before the embryo implants etc. There are lots of quality
control things that can be done which haven't been done yet for human embryo
modification.
It depends on how many embryos you have available. For a normal round of IVF,
you're only looking at like 8 embryo choices. It depends on the parents as well.
If they don't have the mutations in the first place, then there's nothing to
select. I actually think memory is something that should be easier to test for
and figure out. If we really wanted to figure out biological intelligence, then
we should run a long-term large-scale animal breeding experiment where we try to
breed an animal for higher intelligence. We have never done that before, ever.
((Dogs don't count here. Working dogs have specific jobs and while that's
smarter, it's not the same thing as selecting for overall general intelligence.
I'd imagine that kind of dog would be disruptive in the farm work environment
anyway... especially an intermediate along the way to higher intelligence.))
1kanzure2yIf by "CRISPR baby" you mean "every available means" and not specifically
"CRISPR microinjection", then I think there's some IQ points, like the copy
number variation one that showed an increase of 2-3 IQ points per copy, but I
think we can get some good results even without focusing on IQ. For example,
with short sleep you can dramatically increase the number of useful waking hours
throughout an entire lifespan. There's also a single mutation that seems likely
to improve working memory capacity by 19-21% which is quite useful.
I am not that big on "polygenic traits modified through hundreds/thousands of
point mutations". I think there are other interesting things to do. For example,
what if we worked on allowing the neurons to double one more time before
becoming post-mitotic? There are other things for us to look at, I think, other
than GWAS studies.
If regulation, money, and public opinion were no constraint, how many IQ points could a "CRISPR-baby" gain with modern technology?
How much of an issue is the "causal tagging problem" (i.e. knowing that the genes you're editing actually increase intelligence)?
How much of an issue are off target mutations?
How many IQ points could be gained with just embryo selection?