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which method for relative quantitation? - (Nov/30/2006 )

Hello! Here the same problem. We use relative quantitation but often the choise of method is difficult. delta-delta Ct is good but not enough, with n-fold is not always possible to do variance analysis. We also try REST. How do you do?
thanks
Monica

-mo'-

Each method has its own pros and cons, and I don´t think there is a "perfect" method nowadays, it all depends in what your experimental design is like and what are your objectives.
I have used REST and standard curve method, and I personally favor the latter. I don´t like the way the REST method does the stats and normalises the data with the housekeeping. I really dislike the delta delta CT method, but I admit that in certain situations it can be very convenient and adequate.

-erica arborea-

Many thanks we'll try standard curve method with Y= ax+b. Then do you do the ratio between ng of target gene and ng of housekeeping gene? Have you some references about?
thank you very much
monica

-mo'-

Check www.genequantification.com, you'll find fantastic information regarding the different methods to analyse qPCR data, including reviews.
I use relative quantification, therefore I do not calculate amount of cDNA (ng). I relate my unknown samples to an standard curve, obtaining a relative amount for my GOI and same for housekeeping genes. Then I do the ratio between GOI and geometrical mean of my housekeeping genes (I use more than one).

-erica arborea-

THANK YOU VERY MUCH. I know that site, but I never thought about standard curve!.... I'll try with it.
Mo'

-mo'-