Agilent Technologies received US Patent No. 6,558,908, “Methods and kits for indirect labeling of nucleic acids.” The patents covers a method and kit for labeling nucleic acids for use in gene-expression analysis. The process begins with the generation of an oligonucleotide-tagged nucleic acid, which is then hybridized with a complementary tag to yield labeled nucleic acid. The kit described includes a primer for use in enzymatically generating a target nucleic acid. The primer includes an oligo dT region and the tag, and a labeled oligo complement.