Question

Which of the following is a method of gene transfer?
A. Microinjection
B. Particle gun
C. Electroporation
D. All of the above

Answer 1

Hint: The process by which unrelated genetic information is transferred into a cell in the form of DNA is known as gene transfer. One of the aims of gene transfer is to provide patients with therapeutic genes.

Complete Answer:
Once recombinant DNA is made, it needs to be introduced into the host. Gene transfer can be achieved by various methods and it is dependent on two factors - host cell and the vector type. In plants, there are two kinds of gene transfer methods in plants.
1. Direct or vectorless gene transfer
2. Indirect or vector mediated

- Microinjection is the process by which the DNA is injected directly into the nucleus of the plant cell using a fine tipped glass needle or a micropipette. It is an example of direct or vector less gene transfer.
- Particle guns are also known as biolistics or the gene gun method. In this method the foriegn DNA is coated onto the surface of a minute tungsten or gold particles and then bombarded onto the target tissue or cells using the particle gun. This method is an example of direct or vector less gene transfer.
- The process of electroporation involves a pulse of high voltage which is applied to the cells, protoplasts or the tissues which makes transient pore in the plasma membrane. Through these pores, the cells/ tissues/ protoplasts take up the foriegn DNA. Even this method is an example of direct or vector less gene transfer.

Thus, the correct option is D) All of the above.

Note: The importance of gene transfer is that,
- It helps in introducing various important foriegn DNA into the host
- It helps in production of pest resistant plants
- It helps in creating new breeds of plants