Question

1. You have discovered a new tree frog in the rainforest that changes color depending on its environment. You wish to clone the pigment gene responsible for this color change and study its promoter region to understand the regulatory regions involved in its expression.

   1. Would a cDNA library or genomic library be more useful in this situation?

   2. Explain your reasoning in 2-3 sentences

Answer 1

A genomic library is made from a genomic DNA and it represents the entire genome of the organism. Also, genomic libraries are incapable of expressing in prokaryotes like the bacteria as they carry introns. Prokaryotes are incapable of processing introns.

cDNA or the complementary DNA has no introns. Thus, a cDNA copy of gene can be easily isolated as a single and intron free fragment. Working with bacterial genes is easy with this library as prokaryotes do not have introns.