Crispr And Gene Editing: Revolutionizing Modern Medicine
— written by Francis on Jan. 22, 2025, 8:41 p.m.
A revolutionary discovery in medicine with the potential of unlocking new possibilities in understanding and possibly curing genetic disorders. How? By editing or replacing faulty DNA with correctly functioning ones. But what is CRISPR.
DEFINITION OF CRISPR
CRISPR, short for "Clustered Regularly Interspaced Short Palindromic Repeats," is a family of DNA sequences found in the genomes of bacteria and archaea as part of an adaptive immune system. How does it work? I hope you love biology because I'll explaining simply but in detail.
Defense against viruses:
When a bacterium is infected by a virus, it can integrate short sequences of the viral DNA into its own genome at specific locations called CRISPR loci. These sequences, called spacers, serve as a "genetic memory" of past infections.
CRISPR loci consists of:
- Repeats: Short palindromic sequences that are identical.
- Spacers: Unique sequences derived from viral DNA, situated between the repeats.
- Associated Genes (Cas): These encode CRISPR-associated (Cas) proteins that are crucial for the system's function.
So when the bacterium encounters the same virus again, the CRISPR locus is transcribed into a long RNA strand that is processed into small CRISPR RNAs (crRNAs). Each crRNA pairs with a specific sequence of the viral DNA, then guides the Cas protein (commonly called Cas9) to the matching sequence in the viral DNA. Cas9 the cut's the viral DNA neutralizing the threat.
If you read through than and understood, then congratulations, you are now an uncertified biologist.
HOW DO SCIENTISTS AIM TO UTILIZE CRISPR
Scientists have adapted it into a gene-editing tool that uses a guide RNA (gRNA) and the Cas9 protein to target and cut specific DNA sequences. The cell’s repair systems then introduce desired genetic changes using one of these two:
- Non-Homologous End Joining (NHEJ): Repairs the break but often introduces small insertions or deletions (indels), leading to gene disruption.
- Homology-Directed Repair (HDR): If a repair template is provided, the cell uses it to make precise edits to the genome, such as inserting a new gene or correcting a mutation.
APPLICATIONS OF CRISPR IN GENETIC ENGINEERING
Gene Editing: Correcting genetic mutations responsible for diseases like sickle cell anemia or cystic fibrosis leading to cures for such diseases. It also gives hope to finding cures to neurodegenerative diseases like
Huntington’s and Alzheimer’s by targeting the genes linked to them.
red blood cells of sickle cell disease patients
Functional Genomics: Knocking out genes to study their function or understand diseases.
Agriculture: Developing crops with enhanced traits, such as pest resistance, improved yield, or better nutritional content.
Medicine: Engineering immune cells to fight cancer (e.g., CAR-T cell therapy) and developing gene therapies for inherited disorders. It will also allow possibility in curing viral diseases like HIV.
Synthetic Biology: Creating organisms with novel functionalities, such as microbes capable of producing biofuels or pharmaceuticals.
FUTURE OF CRISPR
As researchers refine its accuracy and address ethical concerns, this technology is poised to revolutionize healthcare. Responsible use will ensure that CRISPR remains a tool for progress, offering hope for millions worldwide.
Comments