Gene editing involves making precise and targeted modifications to an organism’s DNA. This technology is utilized for research, therapeutic applications, and potentially for correcting genetic disorders or enhancing specific traits. It is also the method used to apply the age reversal OSK treatments developed by Yamanaka and Sinclair.
CRISPR (Cas9/dCas9) is a treatment that uses a specific immune system from microbes to cut or edit DNA, causing certain genes to be expressed. The Cas9/dCas9 are enzymes; they are like the tool part of CRISPR, and the guide RNA directs them to a specific part of the DNA sequence to perform their task. If the DNA is cut, the cells then heal the DNA using natural processes with a new DNA structure. dCas9 is a modified form of Cas9 and simply causes certain genes to be expressed without cutting the DNA.
“Generally” administering a treatment (such as a CRISPR treatment) in medicine means to apply a treatment indiscriminately to the whole body. A simple way of doing this is with an injection. “Specific” administration is administering a treatment to a specific area, such as when a cream is applied to the skin. CRISPR can be administered by injection, virally, or using nanoparticles; before the organism is born (in vitro), or during its life (in vivo).
CRISPR/dCas9 is often described in papers as being administered with a specially designed Adeno-associated virus (AAV). This viral agent is not dangerous to humans but carries the CRISPR treatment through the cell walls into the cells. It is usually designed to target specific types of cells, such as only certain types of tissues in the eye. Most often, AAVs are used in popular papers because the effects of the attached CRISPR treatment are being studied in specific areas, and the results might be skewed by effects in other areas of the body.
The following study and resource suggest that continual application of the CRISPR/dCas9 OSK treatment throughout the whole body could work to extend lifespan:
https://www.liebertpub.com/doi/full/10.1089/cell.2023.0074 “In the current year-long study, mice with continuous or cyclic OSK expression induced”
https://sinclair.hms.harvard.edu/research “We have developed human-compatible viral vectors to deliver the reprogramming genes to specific tissues or the entire body”
WARNING: As always, gene editing is very specialized and difficult, and it is dangerous if you get it wrong. Aging is not an illness on its own, so getting a license to perform research about curing aging is difficult. There are a lot of complicated steps in performing a treatment like this, and you should not expect to complete the process unless you are a member of a specialized institution.