A polydeoxynucleotide construct is disclosed for use, in conjunction with a DNA-dependent RNA polymerase, as a signal amplifier in nucleic acid hybridization assays. The construct contains a recognition sequence for a target oligonucleotide, a promoter sequence for a DNA-dependent RNA polymerase, and...http://www.google.com.au/patents/US5629153?utm_source=gb-gplus-sharePatent US5629153 - Use of DNA-dependent RNA polymerase transcripts as reporter molecules for signal amplification in nucleic acid hybridization assays