Question

cDNA probes are copied from the messenger RNA molecules with the help of

• A. Restriction enzymes
• B. Reverse transcriptase
• C. DNA polymerase
• D. Adenosine deaminase

Answer 1

Answer: (B)

Reverse transcriptase

cDNA is complementary DNA, a double stranded DNA synthesized using mRNA as a template. This process of conversion of RNA into cDNA is referred to as reverse transcription. The enzyme involved is reverse transcriptase. The difference between DNA and cDNA is DNA contains both introns and exons whereas cDNA contains only exons or coding sequences that are present in the final mRNA transcript. Therefore, cDNA is used instead of DNA in cloning processes.

So, the correct answer is option B.