How does Base Editing work?

Base editing is a form of gene editing that precisely alters single DNA bases, like changing "A" to "G" or "C" to "T", without creating breaks in the DNA. It uses a modified CRISPR-Cas9 system where a CRISPR-associated protein (Cas) is fused to a base-modifying enzyme, allowing for targeted chemical modifications of DNA bases. 

Here's a more detailed explanation:

How it works:

1. 1. Targeting:

   A guide RNA molecule, similar to CRISPR-Cas9, directs the base editing complex to a specific DNA sequence.

2. 2. Base modification:

   The base-modifying enzyme, a deaminase, chemically converts one DNA base into another.

3. 3. Repair:

   Cellular repair mechanisms then take over, ensuring the modified base is correctly incorporated into the DNA. 

Key features:

• Precise:

  Base editing allows for precise changes at the single-base level. 

• No DSBs:

  Unlike traditional CRISPR-Cas9, base editing does not create double-strand breaks (DSBs), which can lead to unintended edits. 

• Versatile:

  Base editors can be engineered to target different base pairs, enabling a range of edits. 

• Therapeutic potential:

  Base editing holds promise for treating genetic diseases caused by single-base mutations.