Question

A giant rat is formed in the laboratory. What could be the possible reason for this? Select the most appropriate option from the following.

• A. Gene replication
• B. Gene synthesis
• C. Gene manipulation
• D. All of the above

Answer 1

The correct option is C Gene manipulation

Gene manipulation is the process of directly manipulating an organism’s genetic material by inserting the desired DNA segment and giving it a desired phenotype. By inserting growth hormone genes into rat embryos under study, transgenic rats can be produced. Such transgenic rats would be gigantic due to overproduction of growth hormone.

Gene replication or DNA replication is the process by which DNA makes a copy of itself before cell division with the help of DNA polymerase. This would not result in the production of giant rats.

Gene synthesis is the process of synthesising artificial genes within the laboratory. Genes for which the nucleotide sequence is known, can be chemically synthesised. Genes for which the nucleotide sequence is unknown, can be synthesised by RNA dependent DNA polymerase. This however, cannot cause the production of giant rats.

Hence, option c (gene manipulation) is the correct answer.