Quality Assessment of cDNA Libraries

A perfect complementary DNA (cDNA) library would provide an accurate and complete representation of all messenger RNA (mRNA) sequences expressed in a particular source, whether a cell, tissue, or organism. Of primary importance during cDNA library construction is the use of a high-quality preparation of RNA, poly (A)⁺ RNA, or other specific subsets of mRNA as starting material for generating a double-stranded DNA copy. Monitoring quality during cDNA synthesis to ensure generation of full-length cDNA is another crucial step in the process. Because only a high-quality cDNA library will yield high-quality data, including valid sequence information, rigorous quality assessment is also needed after library construction (i.e., prior to and during the use of a library for downstream applications). Applying a set of common quality criteria to newly generated cDNA libraries will become increasingly important (1 ).