Prime Editing

Background Information

DNA(deoxyribonucleic acid)is a molecule, located in the nucleus of a cell, shaped like a spiral staircase (double helix), which is a blueprint for all living things. Genes are strands of DNA and each strand is made of millions of particles called nucleotides. Genes are segments of deoxyribonucleic acid (DNA) that contain the code for a specific protein that functions. The genetic code enables a cell to translate the nucleotide language of DNA into the amino acid language of proteins. The strands are a sequence of nucleotides and each sequence forms a different shape.

Prime Editing has three major segments:

  1. The RNA editing guide(pegRNA) finds the target nucleotide sequence and encodes it with the new genetic information.
  2. The Cas9 endonuclease is responsible for nicking the selected part of the DNA.
  3. The engineered reverse transcriptase produces DNA from a single-stranded RNA template.


The cell is first transfected with the pegRNA and the fusion protein. It gets into a cell using a vector which is like a vehicle that carries foreign genetic material into a cell.


CRISPR-Cas9 is another type of genome technology that was discovered before Prime Editing(in 2012) but it had flaws. The CRISPR-Cas9 cut both strands of DNA and relied on the cell’s recovery system to fix itself. When both the strands are cut, there is more space for more insertions. Since they are trusting the cell’s recovery system, there are lots of chances for more mutations where the DNA was cut. Additionally, this was not reliable because sometimes it cleaves the wrong strand.

The Importance of Prime Editing

If we get rid of the mutations in all people who have a disease, we can get rid of most of that disease in the world. This will make sure the next generation has fewer diseases. Some disabilities are also because of genetic mutations and although it has not been done yet, I believe they can also be corrected with Prime Editing.

The Future of Prime Editing

Prime Editing is still in its early stages and has not been used in many diseases. Researchers have had success in correcting the main causes of sickle cell disease and Tay-Sachs disease. In the future, Prime Editing will play a leading role in plant biology and crop improvement which will help greatly with the health of people and starvation.

Key Takeaways:

  • Prime Editing is beneficial to get rid of diseases that are caused by genetic mutations.
  • Prime Editing is more efficient and beneficial than CRISPR-Cas9 as it is more precise and has less collateral damage.
  • Although this technology has been used in a few diseases, more research is needed to improve the technology so that is can clinically solve all the genetically related diseases.



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Varsha Prasad

Varsha Prasad

A student interested in emerging tech