Can current gene editing technologies reverse age related mutations?

[FTM1000]

How can current gene editing technologies like Prime Editing can be used to reverse all age related mutations that negatively affect some type of cell like neurons?. According to this article (you need to click on the "toggle reader view" button in firefox in order to read it without registering to their website) a typical neuron have around 2400 mutations by the age of 80 but only one percent of them are "functional in the sense that they disrupt a protein" so how we reverse those 24 mutations that hurt each of our neurons by the age of 80?, how can we narrow down the number of mutations we need to reverse?. Let's forget about how to overcoming the blood-brain-barrier for now, Let's assume we use a nanotechnology based delivery method(that is being researched today) can we scale up the gene editing process and use it again and again in order to reverse those mutations by guessing what harmful mutations might exist in the neurons?.

There is any current technology capable of identifying specific mutations in some type of cell/tissue in the body without destrorying any cell?. Can it help to narrow down the number of mutations we need to target?.

 

[Drakkith]

My understanding is that current gene editing methods are still far too error prone to be used on people. We need something like an order of magnitude or more reduction in the error rates to start looking at human trials.

There is any current technology capable of identifying specific mutations in some type of cell/tissue in the body without destrorying any cell?

I don't think so. Currently we have to physically and chemically extract the DNA from the cell after its death. Any nanotechnology would have to physically interact with the DNA, which is a vast problem if you're trying to do this in a living cell without harming it since you'd need to compete with existing cell machinery AND do so without interfering with its normal cellular functions. We can't look at it with light, as it's too small, and shorter wavelengths are too energetic to use without severely damaging the cell, so that's out (and that ignores how you'd get the source and/or detector inside of someone or be able to discriminate between adjacent cells).

Quite the problem.

 

[FTM1000]

My understanding is that current gene editing methods are still far too error prone to be used on people. We need something like an order of magnitude or more reduction in the error rates to start looking at human trials.

It seems like some articles suggest that prime editing(or one version of if) can actually have low enough off-target levels.
https://www.nature.com/articles/s41434-021-00263-9
"The absence of DSB formation promises to impart a significant layer of safety to PE-based therapies. Critically, in two independent experiments, Schene et al. failed to detect any off-target edits after performing whole-genome sequence analysis."

"In addition, 5 of 11 HDR founder mice had off-target edits whereas none were reported in the PE2 animals."

but also say "The Schene et al. study critically revealed that unwanted byproducts at the pegRNA or PE3 sgRNA target sites occurred at low rate of 1–4%, in both stem cells and cell lines – an order of magnitude lower than the desired editing efficiency"
is this quote talk about about the same type of Prime Editing as the previous quotes that seems to suggest that at least some type of Prime Editing don't produce any off-target edits?.
The article also say that "it seems inevitable that PE is destined for clinical implementation in the not too distant future".

Can we predict and fix those off-target edits or they are too random for that?.

 

[FTM1000]

I found this part of some article about Prime Editing: https://www.researchgate.net/figure/Validation-of-PE2-off-target-sites-identified-by-Cas9-H840A-nickase-mediated_fig3_344307018
I see that there is data about "relative frequency(off-target activity/on-target activity)" what does it means about Prime Editing? is this the value of off-target edit per intended edits?. why there are multiple values?.

I also found another study: https://academic.oup.com/nar/article/48/18/10576/5907964
which says that "using targeted amplicon sequencing of off-target candidates identified by nDigenome-seq, we showed that only five off-target sites showed detectable PE-induced modifications in cells, at frequencies ranging from 0.1 to 1.9%, suggesting that PEs provide a highly specific method of precise genome editing".
what does it means exactly?, what are those "off-target sites"?. does it means that off-target edits with PE are predictable and can be easily targeted by another gene editing treatment?.

 

[Drakkith]

I'm afraid I'm not nearly experienced enough with this topic to answer your questions.
@Ygggdrasil can you add anything here?