Difference Between Transfection and Transformation

The main difference between transfection and transformation is that the transfection refers to the introduction of foreign DNA into mammalian cells while the transformation refers to the introduction of foreign DNA into bacterial, yeast or plant cells.  

Transfection, transformation, and transduction are the three types of methods through which foreign DNA is incorporated into host cells. Transfection refers to the viral vector-based introduction of foreign DNA.  

Key Areas Covered 

1. What is Transfection
     – Definition, Importance, Methods of Gene Transfer
2. What is Transformation
     – Definition, Importance, Methods of Gene Transfer
3. What are the Similarities Between Transfection and Transformation
     – Outline of Common Features
4. What is the Difference Between Transfection and Transformation
     – Comparison of Key Differences

Key Terms 

Chemical Methods, Gene Transfer Methods, Physical Methods, Transfection, Transformation, Vectors

What is Transfection 

Transfection is the process of artificially introducing DNA or RNA into mammalian cells by means other than viral methods. Most of the times, the piece of DNA of interest is ligated into a vector that can be plasmids, cosmids, BACs (bacterial artificial chromosomes), YACs (yeast artificial chromosomes) or HACs (human artificial chromosomes). The most common transfection methods are chemical-mediated transfection such as calcium phosphate co-precipitation, liposomes, and physical methods such as electroporation, gene gun technique, and microinjection.

Figure 1: Microinjection of a Human Egg

Two types of transfection can be identified based on how long the transferred DNA exist inside the cell. They are transient transfection and stable transfection. In transient transfection, the introduced DNA exists inside the cell for a limited period of time while in the stable transfection, the introduced DNA persists inside the cell for a long period of time as it is integrated into the genome.  

What is Transformation 

Transformation is the natural process of up taking foreign DNA by the competent cells of plant, yeast, bacterial cells. It induces cells to be competent by creating pores on the cell membrane through which naked DNA enters into the cell.

Figure 2: Bacterial Transformation

The three methods of gene transfer by transformation are chemical transformation, electroporation, and particle bombardment. The general method of transformation is the chemical transformation in which the treatment of host cells with calcium-chloride makes the cells more permeable to take up exogenous DNA. This cell stage is called competent cells. Then, pores are created on the cell membrane temporarily by a heat shock. In electroporation, cells are made competent by giving an electric shock. Particle bombardment is the general method of transferring DNA into plant cells in which DNA coated gold or tungsten are forced into the cells physically by a gene gun.  

Similarities Between Transfection and Transformation 

• Transfection and transformation are two types of methods used to introduce foreign DNA into host cells. 
• Introduction occurs through the cell membrane and/or cell wall. 
• Both procedures require naked DNA, which is purified.  
• They may use vectors to facilitate the gene transfer. 
• The three main methods used in the gene transfer are biological, chemical, and physical methods for the gene transfer. 

Difference Between Transfection and Transformation 

Definition 

Transfection is the process of deliberately introducing naked or purified nucleic acids into eukaryotic cells while transformation refers to the direct uptake and incorporation of exogenous genetic material from its surroundings through the cell membrane(s). 

Type of Cells 

The transfection introduces foreign DNA into mammalian cells while the transformation introduces foreign DNA into plant, yeast or bacterial cells. 

Method of Introduction 

Transfection uses calcium phosphate co-precipitation, liposomes, electroporation, gene gun technique, and microinjection for the gene transfer while transformation uses chemical transformation, electroporation, and particle bombardment. 

Conclusion 

The transfection is the introduction of foreign DNA into mammalian cells while the transformation is the introduction of foreign DNA into bacterial, yeast or plant cells. Both methods do not depend on the viral methods of gene transfer. The main difference between transfection and transformation is the type of cell to which the genes are transferred.

Reference:

1. “Introduction to Transfection.” Thermo Fisher Scientific, Thermo Fisher Scientific, Available Here
2. “Transfection.” Choosing the Right Reverse Transcriptase, Available Here
3. “What Is DNA Transformation.” Molecular Cloning Central, GenScript, Available Here

Image Courtesy:

1. “Microinjection of a human egg” By KDS444 – Own work (CC BY-SA 3.0) via Commons Wikimedia   
2. “Artificial Bacterial Transformation” By Amunroe13 – Own work (CC BY-SA 3.0) via Commons Wikimedia