CRISPR & cas9

Everything You Wanted To Know About CRISPR/Cas9 Genetic Scissors

The Royal Swedish Academy of Sciences has awarded the 2020 Nobel Prize in Chemistry to Emmanuelle Charpentier and Jennifer Doudna for their work on CRISPR, a method of genome editing.

A genome is the full set of genetic “instructions” that determine how an organism will develop.

  • Charpentier and Doudna started their study on CRISPR–Cas9 system in 2011.
  • Since then, the field has exploded, inviting interests of many scientists.
  • This technology is simple and affordable; hence, it is being used in different areas.


  • The term CRISPR comes from ‘clustered regularly interspaced short palindromic repeats’.
  • It is distinct genetic sequences found in the genomes of bacteria.
  • Each CRISPR sequence is transcribed into RNA sequences that will target the DNA of a virus.
  • These sequences also include cas (Crispr-associated) genes that code for DNA-cutting Cas enzymes.
  • Together, the guide RNA and Cas enzyme form a complex that hunts out viral DNA and chops it up.
  • The whole CRISPR gene editing tool has been adapted from the immune system of bacteria.

Use Of CRISPR Developed Gene Editing In Different Fields

  • The ability to cut any DNA molecule at a chosen site has huge potential.
  • Gene editing is being used to treat many genetic illnesses.
  • It is also used in agriculture to create disease-resistant crops.
  • The CRISPR gene editing tool can be used to edit a cell’s genome with incredible precision – for example, it can cut out a dysfunctional gene associated with a hereditary illness.
  • And if the healthy version of the gene is also delivered to the cell, the cell’s own repair system will then incorporate the healthy strands at the site where it has been cleaved.
  • This CRISPR tool is often described as “genetic scissors”.
  • Plant researchers have used this tool to develop crops that withstand pests and drought.
  • In medicine, ongoing researches on cancer therapies across the world rely a great deal on this technology.
  • Crispr-delivered genetic modifications can spread through populations of mosquitoes and stop malaria infections.
  • In the current Covid-19 pandemic, CRISPR is being used to develop diagnostic tests. Researchers are working on CRISPE-enabled technology to target the COVD-19’s genome.

Controversy Related To Gene Editing Technology

  • The use of CRISPR has generated significant controversy also.
  • Scientists have utilized the technique to edit genes in human sperm and egg cells.
  • A researcher in China used gene editing on viable human embryos, creating a storm of condemnation and worry about babies “designed” to have particular qualities.
  • Currently, there is no guidelines on the use of CRISPR.
  • However, scientists are unanimous that the gene-editing technique should not be used clinically on embryos.