Analysis of mRNA Expression in Striatal Tissue by Differential Display Polymerase Chain Reaction - Drugs of Abuse: Neurological Reviews and Protocols - page 189

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Analysis of mRNA Expression in Striatal Tissue
by Differential Display Polymerase Chain Reaction
Joshua D. Berke
1. Introduction
1.1. What Is DDPCR?
Differential display polymerase chain reaction (DDPCR) is a technique
that allows comparisons between the expressed mRNA population in two or
more tissues, or in the same tissue under two or more different conditions.
For example, it has been used to discover striatal genes whose expression is
altered following a drug injection (1 , 2) . The essential idea behind DDPCR
is to generate an RNA “fi ngerprint,” a pattern of bands corresponding to the
expressed mRNA population. By performing parallel sets of reactions for
each experimental condition and displaying the resulting fi ngerprints side by
side, bands that differ between conditions can be noted and the corresponding
mRNA identifi ed.
1.2. Why Use DDPCR, Rather than Something Else?
DDPCR has a number of advantages and disadvantages when compared to
other techniques. In contrast to a standard Northern blot, in situ hybridization,
RNase protection assay, or reverse transcriptase-PCR (RT-PCR), it allows
simultaneous analysis of a large number of mRNA species. Compared to
other mass-screening techniques such as subtractive hybridization, when done
properly DDPCR can be extremely sensitive, detecting mRNA differences as
low as twofold or even less. Also, unlike most forms of microarray analysis,
DDPCR makes few assumptions about which mRNAs might be different;
DDPCR can detect wholly novel mRNA species, or novel splice variants of
previously characterized genes. This is especially important now because it has