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Genexpression analses in two different species - how calculate the efficiency (Jan/22/2007 )


I want to analyse the expression of genes in treated and untreadet samples of two different grape species. To anayse, I want use the deltadelta CT method.
For this, first I make a dilution series for each species to get the efficiency of the pcr reaction. So I have two efficiency data.
Now my question: Can I average the two efficieny data to compare the expression of the two species? Or exists there a better method? The problem is, that I must then take a controlgene from of the two species.

Thank you in advanced for help!



Hi Klibi,

think that you definetely have to measure a control gene for every species. But you can surely use the same control gene, no? You can compare the efficiency curves (for example using GraphPad Prism) but I don't think it would be sound to average them and only use one. To compare the gene expression in both species, you should find a control gene that is expressed in both species at a comparable level (but maybe ther is something in the literature). If you find this control gene, you can compare both species by analyzing the deltaCT values of your gene of interest.

Hope that helps,