Horizontal gene transfer (HGT)

Definition

Horizontal gene transfer (HGT) is the movement of genetic material between organisms other than through vertical inheritance (parent to offspring). This process contributes significantly to genetic diversity in prokaryotes.

5 Must Know Facts For Your Next Test

1. HGT can occur through transformation, transduction, and conjugation.
2. It allows for the rapid acquisition of new traits, such as antibiotic resistance.
3. Transformation involves uptake of naked DNA from the environment.
4. Transduction is mediated by bacteriophages transferring DNA between bacteria.
5. Conjugation involves direct cell-to-cell contact for DNA transfer, often via plasmids.

Review Questions

• What are the three main mechanisms of horizontal gene transfer?
• How does HGT contribute to antibiotic resistance in bacteria?
• What role do bacteriophages play in HGT?

Related terms

Transformation:

A form of HGT where bacteria take up naked DNA from their surroundings.

Transduction:

A form of HGT where bacteriophages transfer genetic material between bacteria.

Conjugation:

A form of HGT involving direct cell-to-cell contact, typically through a pilus and plasmid exchange.