Question

Which of the following can distinguish transformants from non-transformants?

• A. Presence of more than one recognition site in the vector DNA
• B. Presence of foreign DNA in the vector DNA results in insertional inactivation of selectable markers
• C. Antibiotic-resistance gene gets inactivated due to insertion of foreign DNA
• D. Both 2 and 3

Answer 1

Answer: (D)

Selectable markers help in detecting and selectively permitting the growth of the desired transformants.

Insertional inactivation is a technique where foreign DNA is inserted into a restriction site inside an antibiotic resistance gene causing the gene to get inactivated.