PCR Arrays are amongst the most reliable tools for analysing the expression of a focused panel of genes, particularly if the researcher is more familiar with real-time PCR-based techniques than microarray-based methods.
SuperArray's RT2Profiler PCR Array is a 96-well plate containing primers for a thoroughly researched panel of relevant, pathway or disease-focused genes plus appropriate positive and negative controls. The Arrays now encompass over 36 different human and mouse pathways or disease states.
"Focused gene expression analysis by real-time PCR is increasingly used during the pharmaceutical screening process," said David Martz, director of Sales and Marketing at SuperArray Bioscience.
"From target identification and evaluation, to optimisation and development, the expression pattern for specific subsets of genes needs to be characterised and monitored."
Many researchers have been hesitant to try microarray-based gene expression profiling methods due to the multiple steps involved that can introduce greater variability in the results, relative to real-time PCR.
Even after successfully screening a genome-wide or pathway-focused panel of genes on a microarray, manuscript and grant reviewers require validation of the microarray results by real-time RT-PCR before publication or funding.
The next technology for gene expression analysis should feature the profiling capabilities of microarray and the quantitative nature of real-time PCR.
Development of such a "PCR Array" technology brings with it complex challenges including the choice of a detection method, careful primer design, master mix optimisation, and gene content decisions.
Detection based on SuperArray's SYBR Green, the intercalating fluorescent dye, is the least expensive and easiest method available.
Most real-time systems detect and accommodate SYBR Green making the method very flexible and widely applicable. However, SYBR Green detects any double-stranded DNA non-specifically.
Therefore, reactions must generate single, gene-specific amplicons without the coamplification of non-specific secondary products making primer design very critical.
"Our catalogued PCR Arrays focus on disease states and biological pathways important for general candidate screening purposes, like cancer and diabetes, or apoptosis and toxicology. We also produce custom PCR Array plates with gene lists for individual discovery and development projects," added Martz.