PCR-intel control - (Sep/21/2008 )
WHy do we need an internalloading control e.g. GAPDH or b-actin for PCR reactions?
you mean for qPCR ?
do you know what you are doing ?
To answer your question : it's not always required, you can also standardize your results to the amount of starting template if your control genes are not behaving like you expect them to. If you are doing qPCR to determine changes in expression of a gene, you usually use one or multiple control genes such as "housekeeping" genes because in theory their expression should remain constant throughout your experiment. Then you can set the value you found for your control gene as "100% expression" and see if your gene of interest is up- or down-regulated.
But maybe you are not doing qPCR and I am waisting my time.