Complementary DNA or in short cDNA is the product of reverse transcription from an RNA template. Typically, mRNA serves as template for the generation of a cDNA in which its poly-(A) tail is used as a primer site for reverse transcriptase. Subsequently, the cDNA product is amplified by PCR. Usually cDNA does not contain any introns and corresponds oftentimes to the actual coding sequence of gene. As such, cDNA is an important intermediate on the way to expressing a protein of interest. A complete cDNA library of a given organism represents its transcriptome. Derived from mRNA and including 5’ and 3’ UTRs, our cDNA collections are ideal for overexpressing a gene in the context of native regulation.