The ability to study comparatively the expression of messenger RNA (mRNA) populations from different samples has become accessible by the novel application of reverse transcription (RT), together with the polymerase chain reaction (PCR), to isolate gene sequences which can then be visualized by displaying on a sequencing gel. Differentially expressed transcripts can be analysed by Northern blotting or semiquantitative PCR to confirm differential expression. Utilization of various primer combinations facilitates the isolation of approximately 15 000 mRNA species, which represents gene expression in a mammalian cell at any one time.
Keywords: mRNA






