RT-PCR (reverse transcription-polymerase chain reaction) is the most sensitive technique for mRNA detection and quantitation currently available. Compared to the two other commonly used techniques for quantifying mRNA levels, Northern blot analysis and RNase protection assay, RT-PCR can be used to quantify mRNA levels from much smaller samples. In fact, this technique is sensitive enough to enable quantitation of RNA from a single cell. We have a Roche LightCycler® 480 Real-Time PCR System with an interchangeable silver thermal block cycler unit. Users can flexibley switch between 96- and 384-mulitiwell plate formats. The system is operated by a separate desktop data station based on Windows XP.