A method, based on the polymerase chain reaction, used to identify genes differentially expressed in various tissues or in normal vs pathological states. The messenger RNA from the two samples is reverse transcribed, amplified with rather nonspecific primers, and run on a high-resolution gel. Bands unique to single samples are considered to be differentially expressed and can be used to clone the full-length cDNA. Superseded by gene chip technologies. See also differential screening.
Subjects: Chemistry — Medicine and Health.