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Can we compare traditional RT-PCR results with Real Time RT-PCR? - (Jul/15/2007 )

Hi, I have performed both real time RT-PCR (using Syber Green, ddCt method) and traditional RT-PCR (quantifying bands) for the same samples.

In real time RT-PCR, my target gene shows >100 fold increase compared to Control whereas using traditional RT-PCR methods, I only get around 7 fold increase.
I have repeated the experiments and results are quite consistent. Therefore I would like to know whether this is normal, that we can't compare the results from these two RT-PCR methods, or I really did something wrong in either one of the methods?

Thank you


As far as I know, traditional RT-PCR is only semi-quantitative, i.e. it can only tell you if something is up- or down-regulated, but you should not conclude too much about the extent... If your sybr-green primers are established, and well set-up ones, I'd trust those more regarding the extent of up-regulation.