Certified GKH Gardening Expert
If all of the tubers that you have planted are Labeled Desiree, then most likely they are. There can be quite a bit of variation. There is a chance that they were mislabeled, but this would have been apparent at the time of planting. It will be best to contact the vendor that you had purchased them from to obtain more information.
This article will offer more information on proper potato planting: