Gene editing is a rapidly developing area of biotechnology, it allows the precise change of the nucleotide sequence of the genome of living cells.
What is Genome editing?
Genome editing is a technique used to precisely and efficiently modify DNA within a cell leading to changes in physical traits, like eye color, or disease risk.
The technique involves making cuts at specific DNA sequences with enzymes known as ‘engineered nucleases’.
The technology can be used to add, remove, or even alter DNA in the genome.
By editing the genome, the characteristics of a cell or an organism can be changed easily.
How is it done?
Genome editing uses a type of enzyme called an ‘engineered nuclease’ which cuts the genome in a specific place.
Engineered nucleases are made up of two parts:
Nuclease part: A nuclease part that cuts the DNA.
DNA-targeting part: A DNA-targeting part that is designed to guide the nuclease to a specific sequence of DNA.
After cutting the DNA in a specific place, the cell will naturally repair the cut.
Scientists can manipulate this repair process to make changes (or ‘edits’) to the DNA in that location in the genome.
Which genome editing technologies are currently in use?
Current genome editing technologies include zinc-finger nucleases (ZFNs), transcription activator-like effector-based nucleases (TALENs), and clustered regularly interspaced short palindromic repeats (CRISPR), with CRISPR-associated nucleases (Cas).
CRISPR-based genome editing is considered more precise (it is possible to target specific sequences of DNA), more efficient (it has relatively few off-target effects), and cheaper to use than other genome editing technologies.
CRISPR-Cas9
CRISPR-Cas9 is the most common, cheap, and efficient system used for genome editing.
CRISPR stands for ‘clustered regularly interspaced short palindromic repeats.
CRISPR is the DNA-targeting part of the system which consists of an RNA molecule, or ‘guide’, designed to bind to specific DNA bases through complementary base- pairing.
Cas9standsforCRISPR-associated protein 9 and is the nuclease part that cuts the DNA.
The CRISPR-Cas9 system was originally discovered in bacteria that use this system to destroy invading viruses.
Genome Editing
Context:
Gene editing is a rapidly developing area of biotechnology, it allows the precise change of the nucleotide sequence of the genome of living cells.
What is Genome editing?
How is it done?
Which genome editing technologies are currently in use?
CRISPR-Cas9