How does Ct value relates to the quantity of DNA present in the sample?

Question

How does Ct value relates to the quantity of DNA present in the sample?

Answer 1

There is a linear relationship between the Ct value and the log of the standard for a dilution series. Consequently, if the dilution series has been prepared correctly, plotting Ct against log standard gives a straight line. This is the standard curve used to measure the quantity of target in ‘unknown’ samples. Comparing the Ct of unknown samples against the standard curve allows calculation of the initial amount of target used in real-time RT-PCR.

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