I have some samples to be injected to mice, I wanted to note that these sample can contain certain cancer related mRNAs. I just wanted to say which genes was 'expressed' in my samples, so I wonder if it is okay to say it is expressed when the read count is 1 or more and not if the read count is 0. I just need to loosely say about the expression without claiming the quantity or anything (For that, it will be validated with qPCR later if needed).

To my understanding, for example, in micro-array, I cannot claim that a gene is expressed because there are background signal so the low positive number does not imply expression, but 'reads' are only mapped to a single unique gene to get gene count and there is no background. Please suggest if this is an okay practice to be able to simply say if particular mRNAs exist in the samples.