A technique for amplification of a DNA sequence, based on the steps of retroviral replication of nucleic acids. Beginning with a clean DNA sequence, DNA-dependent RNA polymerase makes a RNA transcript; from this, a DNA transcript is made by reverse transcriptase. Because the RNA of the RNA-DNA hybrid which is produced by the reverse transcriptase is degraded by RNaseH, amplification is linear, not exponential. see polymerase chain reaction; see strand displacement amplification