
CRISPR Can Now Edit Genes Using Nanoparticles Instead of Viruses - rbanffy
https://motherboard.vice.com/en_us/article/ywbkzw/crispr-virus-nanoparticle-mit-rna?utm_source=mbtwitter
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lukeschlather
From the paper, it sounds like the particle they constructed is about 120nm in
diameter. So a bit larger than the viruses previously used. Which are also
nanoparticles, so I guess it's more that this delivery system isn't based on a
virus.

I guess, one thing I don't quite understand: are the viruses used in CRISPR
really viruses (can they self-replicate using the cells they alter?) Or are
they just nanomachines based on viruses?

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88e282102ae2e5b
The viruses used to deliver CRISPR in the past are not able to replicate.
They're so small that you have to remove all of the viral DNA in order to even
fit your CRISPR-coding genes inside.

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Dowwie
Why is there a gene for high cholesterol? In what kind of environment was high
cholesterol beneficial?

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anvandare
Not all genes have to have a function, or even a beneficial one. DNA could be
riddled with legacy (inactive) code. As long as there's not enough
evolutionary pressure -its negative value doesn't pass a threshold- the code
would be retained.

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stochastic_monk
Consider an extremely high-dimensional feature space [not just genes, but
transcripts/isoforms (differently diced-up versions of RNAs with different
functions), hosts of active-but-not-transcribed-into-proteins RNAs, and
dynamic regulation through interactions] which updates a reinforcement
learning algorithm one epoch per generation (~20-30 years), and you'll see why
it's far from optimized.

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theddman
This article doesn't touch on how they also used mRNA coding for Cas9 instead
of the protein itself.

