Hi all, I want to test differential expression among (cond1+cond2)/2 and cond3. I understand a contrast of (-0.5,-0.5,1) will do this, subsequently I should also be able to detect if cond3 is significantly close to (cond1+cond2)/2, cond1 or cond2. I`m looking for a p-value for each of these comparisons, so I want to classify my cond3 expression values into 3 groups 1 . cond1 like but not (cond1+cond2)/2 like. 2. (cond1+cond2)/2 like but not cond1 like and not cond2 like. 3. cond2 like but not (cond1+cond2)/2 like. Of course there will be cases where genes can outside these groups but these 3 groups are what mainly interest me. I hope I could explain, some guidance is greatly appreciated. Thanks, Al [[alternative HTML version deleted]]