Skip to main content

CRISPR-Cas9 - The Gene Editing Revolution

 Introduction

  • CRISPR-Cas9  is a revolutionary gene editing technology that has transformed the field of molecular biology and genetics.
  • This lecture will explore the principles, mechanisms, applications, and ethical considerations of CRISPR-Cas9 gene editing.

Learning Objectives

By the end of this lecture, you should be able to:

  1. Understand the fundamental principles of CRISPR-Cas9 gene editing.
  2. Describe the mechanisms of CRISPR-Cas9 technology.
  3. Recognize the applications and implications of CRISPR-Cas9 in various fields.

Principles of CRISPR-Cas9 Gene Editing

1. CRISPR-Cas System:

  • CRISPR  stands for Clustered Regularly Interspaced Short Palindromic Repeats. It's a natural defence mechanism in bacteria and archaea against invading viruses.
  • Cas9  is an enzyme that acts like molecular scissors, cutting DNA at specific locations.

2. Targeted Gene Editing:

  • CRISPR-Cas9  allows precise modification of genes by guiding Cas9 to a specific DNA  sequence using a guide RNA (gRNA).
  • The gRNA is designed to complement the target gene's sequence.

3. DNA Repair Mechanisms:

  • After Cas9 cuts the DNA, cells use two primary repair mechanisms: Non-Homologous  End Joining (NHEJ) and Homology-Directed Repair (HDR).
  • NHEJ  can introduce random mutations, while HDR allows precise gene editing.

Mechanisms of CRISPR-Cas9

1. gRNA Design:

  • The gRNA is designed to be complementary to the target gene's sequence.
  • It guides Cas9 to the precise location for gene editing.

2. Cas9 Cleavage:

  • Cas9  creates a double-stranded break in the DNA at the target site.
  • This break triggers the cell's repair machinery.

3. DNA Repair:

  • NHEJ can introduce insertions or deletions (indels), causing gene disruption.
  • HDR can be used to introduce specific changes or insert new genetic material.

Applications of CRISPR-Cas9

1. Biomedical Research:

  • CRISPR-Cas9  is used to study gene function and develop disease models.
  • It accelerates drug discovery and drug testing.

2. Genetic Diseases:

  • CRISPR-Cas9 has the potential to treat genetic disorders by correcting disease-causing mutations.
  • Clinical trials are ongoing for conditions like sickle cell anaemia and beta-thalassemia.

3. Agriculture:

  • CRISPR-Cas9      can create genetically modified crops with improved traits like disease resistance or higher yield.
  • It can reduce the need for chemical pesticides.

4. Ethical Considerations:

  • The use of CRISPR-Cas9 in humans raises ethical questions about designer babies, unintended consequences, and access to the technology.

Conclusion

  • CRISPR-Cas9 is a groundbreaking gene editing technology that enables precise modification of DNA.
  • Its applications in research, medicine, and agriculture are vast, but ethical considerations are crucial.

Key Takeaways

  • CRISPR-Cas9  is a gene editing technology that uses Cas9 enzyme guided by gRNA to cut DNA at specific locations.
  • Repair mechanisms like NHEJ and HDR can be used to introduce mutations or precise changes.
  • CRISPR-Cas9  has applications in research, genetic diseases, agriculture, and beyond,  but ethical concerns must be addressed.

Labels:

Comments

Post a Comment

Popular posts from this blog

Active Transport

  Active Transport Active transport is a vital biological process that enables cells to move ions and molecules against their concentration gradients, from regions of lower concentration to regions of higher concentration. This lecture will explore the principles, mechanisms, and importance of active transport in various physiological processes. Key Concepts of Active Transport Energy Requirement : Active transport requires energy input, usually in the form of adenosine triphosphate (ATP) or a proton gradient generated by primary active transport. This energy is used to move substances against their concentration gradients. Ion Pumps and Transporters : Active transport is carried out by specialized proteins known as ion pumps or transporters. These proteins actively move ions and molecules across cell membranes or within cellular compartments. Concentration Gradients : Active transport serves to maintain or establish concentration gradients of specific ions or molecules. These grad...
Post a Comment
Read more

Metabolism of Carbohydrates QnA

Short Questions and answers of Metabolism of Biomolecules   Topic - Carbohydrate metabolism : Glycolysis  and its regulation 1. What is glycolysis?    Answer: Glycolysis is a fundamental metabolic pathway in which glucose is broken down into two molecules of pyruvate, generating ATP and NADH in the process. 2. Where does glycolysis take place in the cell.    Answer: Glycolysis occurs in the cytoplasm of the cell. 3. What are the main substrates and products of glycolysis? Answer: The substrates of glycolysis are glucose, and the products are two molecules of pyruvate, two molecules of NADH, and a net gain of two ATP molecules. 4. What is the role of ATP in glycolysis?    Answer: ATP is both consumed and generated in glycolysis. Two ATP molecules are used in the early steps of glycolysis, and four ATP molecules are produced, resulting in a net gain of two ATP molecules. 5. What is the significance of NADH in glycolysis?   ...
Post a Comment
Read more

Concepts of Biomolecules

Introduction Biomolecules are the molecules that make up the essential components of living organisms. They play crucial roles in various biological processes and are fundamental to life itself. Classification of Biomolecules Biomolecules can be broadly categorized into four major groups: Carbohydrates : Carbohydrates are organic compounds composed of carbon, hydrogen, and oxygen in a 1:2:1 ratio (CH2O). They serve as a primary source of energy and provide structural support in cells. Examples include glucose, cellulose, and glycogen. Lipids : Lipids are hydrophobic molecules that include fats, oils, and phospholipids. They function as energy storage molecules, cell membrane components, and signalling molecules. Examples include triglycerides, phospholipids, and cholesterol. Proteins : Proteins are complex macromolecules composed of amino acids. They have diverse functions, including enzyme catalysis, structural support, transport, and signaling. Examples include enzymes, antibodies, a...
Post a Comment
Read more