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Ct variation in the internal control - (Oct/03/2005 )

Hi!

I want to know which level of difference is acceptable for an internal control between the control sample and the treated sample. I use GAPDH and, for instance, in the control sample the Ct is 20 and in the treated one is 20.2, which I think is correct. But in other cases, the Ct is 20 in the control and 21 or 22 in the treated. Which is the limit of difference I can accept? 0.5 cycles? 1 cycle?

Thank you very much!

Neus

-Neus-

QUOTE (Neus @ Oct 3 2005, 01:13 PM)
Hi!

I want to know which level of difference is acceptable for an internal control between the control sample and the treated sample. I use GAPDH and, for instance, in the control sample the Ct is 20 and in the treated one is 20.2, which I think is correct. But in other cases, the Ct is 20 in the control and 21 or 22 in the treated. Which is the limit of difference I can accept? 0.5 cycles? 1 cycle?

Thank you very much!

Neus



Hello, I have the same question actually. Are there any articles on this issue?

-StaticApnea-

QUOTE (Neus @ Oct 3 2005, 04:13 AM)
Hi!

I want to know which level of difference is acceptable for an internal control between the control sample and the treated sample. I use GAPDH and, for instance, in the control sample the Ct is 20 and in the treated one is 20.2, which I think is correct. But in other cases, the Ct is 20 in the control and 21 or 22 in the treated. Which is the limit of difference I can accept? 0.5 cycles? 1 cycle?

Thank you very much!

Neus

Hi Neus,
maybe you should use a different internal control, like 28s rRNA. Actin and metabolic enzymes are always critical, although everywhere published, since they become regulated easily.
Cheers,

ophris

-ophris-