Gene Expression

Real-time PCR (qPCR) is the preferred method for DNA and cDNA quantification due to its high sensitivity, reproducibility and wide dynamic range. Relative quantification using qPCR measures the changes in steady-state mRNA levels of a gene across multiple samples normalized to a reference gene(s), often referred to as the housekeeping gene(s). In theory, the expression levels of the housekeeping gene should remain stable in the tissues or cells under investigation, or in response to the experimental treatment. In practice, there is considerable evidence that housekeeping gene expression varies significantly. Despite the precision of qPCR, conclusions drawn from gene expression experiments are often misleading due to differences in amplification efficiency between the gene of interest and the housekeeping gene(s).

To address these issues, Kapa Biosystems has evolved the first DNA polymerase specifically for SYBR® Green I-based qPCR through a process of directed evolution. The KAPA SYBR DNA Polymerase exhibits improved speed, processivity, and robustness resulting in consistently high amplification efficiencies regardless of amplicon length and GC content, which is required for accurate relative quantification. In addition, our probe-based qPCR Kit has been specifically optimized for versatility and speed and is ideally suited for gene expression studies.

Available Products


  • Increased speed, processivity, and robustness
  • High reaction efficiencies regardless of amplicon length and GC content


  • Compatible with sequence-specific 5′-hydrolysis (TaqMan®) probes, FRET probes, and molecular beacons
  • Fast, reproducible, and precise quantification