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CT value of reerence gene - what should be the GAPDH Ct value (Nov/04/2008 )


I'm new to qPCR. How do I determine which dilution to work with? I'm using GAPDH as my reference gene and thus what should be teh range of my Ct value?



You can only determinate from testing it on your sample. Generaly good Ct values for quantification are between 15 and 30 for a reference gene. I't important to have a similar level of expression for your gene of interest and the reference genes.

I usually use 2 ul of a 20ul RT reaction (Roche Transcriptor), where I put 1ug of RNA.