ABSTRACT
The differential display method is a polymerase chain reaction-based method, and thus has the potential to identify very low levels of gene expression and hence rare species of messenger RNA (mRNA). A major advantage of differential display is that less than 5 mg of total ribonucleic acid (RNA) is needed to amplify all the mRNAs in a given cell type. In contrast, other methods of studying gene expression require 20-100 times more total RNA. Stimulated and control tissues are homogenized and their total RNA extracted. Northern blot analysis, where the original RNA samples is electrophoresized, transferred to a membrane and probed with the radiolabelled candidate, thus determining whether the candidate is differentially expressed due to the stimulation. A differentially expressed candidate can be identified by the sequence of its bases. The candidate has to be cloned prior to sequencing. This allows the addition of known sequences of Deoxyribonucleic acid at either end of the candidate, which are essential for sequencing.
