NEWS –  Indian scientists from CSIR-IGIB and L.V. Prasad Eye Institute developed an improved CRISPR system using the FnCas9 enzyme for more precise and efficient genome editing.

HIGHLIGHTS

• CRISPR Basics: CRISPR-Cas9 technology, adapted from bacterial defense mechanisms, allows targeted modification of DNA sequences. Traditional SpCas9 can cause off-target effects, leading to unintended genetic changes.
• FnCas9 Overview: FnCas9, derived from Francisella novicida, offers higher precision than SpCas9 but initially had lower efficiency.
• Modifications to FnCas9:
  • Amino Acid Changes: Enhanced FnCas9 with modified amino acids for better binding affinity to DNA.
  • Increased Efficiency: The modified enzyme shows improved activity and flexibility, making it more effective in editing difficult-to-reach genomic regions.

Experimental Results

• Performance:
  • Higher Efficiency: Enhanced FnCas9 outperforms unmodified FnCas9 and SpCas9 in DNA cutting rates and accuracy.
  • Diagnostic Application: More effective at detecting single-nucleotide changes, broadening its diagnostic capabilities.

Therapeutic Applications

• Testing for Genetic Disorders:
  • Inherited Blindness: Enhanced FnCas9 successfully corrected a mutation causing Leber congenital amaurosis type 2 (LCA2) in lab-grown retinal cells, showing minimal off-target effects.

Future Directions

• Patent and Development:
  • Indigenous Patent: Indian researchers aim to patent the technology to reduce dependency on foreign licenses and lower costs for developing new therapeutics.
  • Next Steps: Focus on optimizing delivery methods and further reducing the enzyme’s size.

Key Points

• Advantages Over SpCas9: FnCas9 offers greater specificity and fewer off-target effects, enhancing the safety and reliability of genome editing.
• Enhanced Functionality: Modified FnCas9 exhibits higher efficiency and accuracy in gene editing, supporting its potential for therapeutic use and diagnostics.