Unlocking the Future: How Gene Editing is Revolutionizing Medicine

 

        GENE EDITING

Written by T. Divya

WHAT IS GENE EDITING?

Gene editing is the process of making precise alterations to the DNA sequence of a living organism, effectively customizing its genetic makeup. This process is carried out using specialized enzymes, particularly nucleases designed to target specific DNA sequences. These nucleases create cuts in the DNA strands, which allow for the removal of existing DNA and the insertion of new DNA. 

A prominent gene-editing technology is CRISPR-Cas9, a revolutionary tool identified in 2012 by American scientist Jennifer Doudna, French scientist Emmanuelle Charpentier, and their colleagues, and further developed by American scientist Feng Zhang and his team. CRISPR-Cas9 operates remarkably, enabling scientists to delete and replace DNA at targeted locations.

Gene Editing Mechanisms

1. CRISPR-Cas9: 

•      CRISPR, or Clustered Regularly Interspaced Short Palindromic Repeats, is a system bacteria use to fend off viruses. Cas9, an enzyme, functions as molecular scissors, cutting DNA at designated sites.
•       Guide RNA (gRNA) steers Cas9 to the exact DNA location needing edits, 

      enabling precise genetic material alterations.

       

     2.TALENs (Transcription Activator-Like Effector Nucleases):

•      These custom-made proteins latch onto specific DNA segments, causing a 

     double-strand break.

      The subsequent repair can modify the genetic sequence.

      3. ZFNs (Zinc Finger Nucleases):

• ZFNs, akin to TALENs, are custom proteins that bind to particular DNA segments and introduce double-strand breaks to edit genes.

Gene Editing Applications

1. Medical:

• Gene Therapy: Corrects defective genes to treat genetic conditions such as cystic fibrosis, muscular dystrophy, and sickle cell anemia.
• Cancer Treatment: Modifies immune cells to enhance their ability to identify and eliminate cancer cells.

     2. Agriculture:

•  Breeds crops with greater resistance to pests, diseases, and environmental stressors.
• Boosts crops' nutritional value and productivity.

     3. Scientific Research:

• Generates model organisms for studying diseases, mechanisms, and potential cures.
• Explores gene functions and interactions.

Ethical and Regulatory Considerations

• Ethical Issues: Risks include accidental changes in other genome areas (off-target effects) and the ethical debate surrounding gene editing in human embryos and the creation of "designer babies."
• Regulation: Gene editing usage and research regulations differ across countries, with evolving frameworks to guarantee ethical and safe technology application.

Current Status

• Research and Development: Gene editing predominantly remains in the research and development phase.
• Commercial Use: Some gene-edited crops and other products have been approved for commercial use, particularly in agriculture.