In this study, we report that a simple quantitative PCR (qPCR) by measuring intronic genomic Gapdh copies of human Gapdh (hGapdh) and murine Gapdh (mGapdh) that can quickly quantify if a tumor or a cell line is of human or murine origin, or a mixture with high sensitivity and within a time frame of a few hours. Here, GAPDH is linked to neoplasm.