Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
qPCR, or quantitative PCR, is a laboratory technique used to amplify and simultaneously quantify a targeted DNA molecule in real-time. It allows researchers to measure the amount of a specific DNA sequence in a sample.
5 Must Know Facts For Your Next Test
qPCR uses fluorescent dyes or probes to detect and quantify DNA as it is amplified.
It can be used to quantify gene expression levels by measuring RNA after it's converted to cDNA.
The technique involves cycles of denaturation, annealing, and extension similar to traditional PCR but with real-time data collection.
qPCR data are often presented as Ct values, which represent the cycle number at which the fluorescence signal exceeds the background level.
It is highly sensitive and can detect low levels of nucleic acids in a sample.