Lecture on Genetics and Gel Electrophoresis

Introduction to Genetics

• Early misconceptions about genetics:
  • Belief that offspring are simple blends of two parent organisms.
• Example: Guppies in aquariums demonstrate inheritance and genetic traits.

Guppy Traits and Genetic Observation

• Guppies:
  • Freshwater fish with live births.
  • Produce a large number of offspring.
  • Exhibit various traits carried by DNA.
• Challenge: Tracking genetic inheritance due to multiple mothers in the tank.

Biotechnology

• Definition: Integration of biology and technology.
• Constantly evolving field including:
  • PCR (Polymerase Chain Reaction).
  • Cloning.
  • Genetic engineering.

Gel Electrophoresis

• Use: Separate molecules (particularly DNA) based on size.
• DNA Structure:
  • Negative charge due to phosphates in nucleotides.
• Gel Electrophoresis Process:
  • Machine applies electrical charge through an agarose gel.
  • DNA placed in wells at the negative end and moves toward the positive side.
  • Movement dependent on DNA piece size.

Role of Restriction Enzymes

• Used to cut DNA at specific sites.
• Allows comparison of DNA fragments from different samples (e.g., mother and baby guppy).
• Differences in DNA fragment sizes indicate genetic variation.

Interpreting Gel Electrophoresis Results

• DNA bands: Different sizes after separation.
• Use of stain and UV light to visualize bands.
• DNA Ladder:
  • Known fragment sizes used as a reference.

Applications of Gel Electrophoresis

• Determining genetic relatedness among species.
• DNA fingerprinting for crime scene investigations.
• Further analysis through methods like Southern blotting.

Conclusion

• Gel electrophoresis is a key tool in biotechnology.
• Important for research and practical applications.
• Encouragement to stay curious and explore further topics.