Unsual qPCR curve

[LobsterFarmer]

Ive been using a custom made mastermix that for some reason results in a qPCR curve that has a baseline lift. I have attached a crude drawing of what the graph looks like. Due to the baselift lift the CP values are really early, as early as cycle 15.

Playing with the initial denaturation temp, denaturation and annealing steps didnt solve the problem.

Any help would be greatly appreciated.

Thanks

 

[CharonY]

Hard to tell without looking at the actual data, but two possibilities are high template concentration leading to the software messing up baseline correction or, conversely, low concentration/inefficient reaction, starting off with non-exponential replication until template concentration reaches a threshold to allow higher amplification rates. The latter is rather unusual, though. First thing to test would be a dilution of the sample and see how the curve shifts.