To take into account the possibility of inter-individual variations in the expression of mRNAs and proteins for IFNAR, we compared the mRNA and protein expressions between paired tumor (T) and non-tumor (N) kidney samples, and the relative yield of the PCR product from the tumor to that from the corresponding non-tumor tissue (T/N) for the expression of IFNAR1 and IFNAR2 mRNAs was calculated as described previously [9,10]. The gene discussed is IFNAR1; the disease is neoplasm.