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CT value too small - (Aug/24/2011 )

Hi all.

I am new to real time PCR.
Recently, I am doing real tine PCR on a plasmid containing a mutated gene. Then I use 2ng/ul plasmid to do a real time pcr using SYBgreen. However, I get a Ct value of 6 . I just wonder whether Ct is too small. And is it bad or does it have any implication if the Ct value is too small?


Yes, 6 is really too small. You should dilute your plasmid at least 1000x to get values between 15 and 30, that are suitable for quantification.