PCR

Definition

Polymerase Chain Reaction (PCR) is a molecular biology technique that amplifies specific DNA sequences exponentially through repeated cycles of heating and cooling. The process uses a thermostable DNA polymerase enzyme, primers complementary to target sequences, and nucleotides to generate millions of copies from a single DNA template. Each cycle consists of three steps: denaturation (separating DNA strands at ~95°C), annealing (primers binding at ~50-65°C), and extension (polymerase synthesizing new strands at ~72°C). PCR is fundamental for gene cloning, sequencing, diagnostics, forensics, and gene expression analysis. Variants include quantitative PCR (qPCR) for measuring gene expression, reverse transcription PCR (RT-PCR) for RNA analysis, and digital PCR for absolute quantification.

Visualize PCR in Nodes Bio

Researchers can visualize PCR-based experimental workflows as networks connecting primers, target genes, and downstream applications. Map relationships between PCR validation results and gene expression data across multiple samples. Create networks linking PCR-confirmed genetic variants to phenotypes, pathways, or disease outcomes. Visualize primer design strategies by connecting target sequences to genomic regions and associated biological functions.

Example Use Case

A cancer genomics team uses PCR to validate EGFR mutations identified through next-generation sequencing in lung cancer patients. They design specific primers for exons 18-21, perform PCR amplification, and confirm activating mutations L858R and exon 19 deletions. The validated mutations are then connected to patient response data for tyrosine kinase inhibitors. By visualizing PCR-confirmed mutations alongside clinical outcomes and pathway data, researchers identify mutation patterns predictive of treatment resistance and discover co-occurring alterations in downstream signaling molecules.

Related Terms