Which one of the following step is not involved in the genetic modification of an organism?

Cutting of DNA with DNA ligase

The correct answer is Option (2) → Cutting of DNA with DNA ligase    

Explanation:

1. Identification of DNA with desirable genes – This is a required step in genetic modification. You need to find the gene you want to insert.
2. Cutting of DNA with DNA ligase – This is NOT correct.
• DNA is cut using restriction enzymes (also called restriction endonucleases), not DNA ligase.
• DNA ligase is used to join DNA fragments, not cut them.
3. Introduction of the identified DNA into the host – This is part of the process, usually done using a vector or techniques like transformation.
4. Maintenance of introduced DNA in the host and transfer to progeny – This is essential to ensure the trait is inherited.

So, correct answer is Cutting of DNA with DNA ligase.