PCR (polymerase chain reaction) facilitates the in vitro amplification of DNA fragments. This has a wide range of applications in diagnostics, genotyping, forensics, mutation detection, paternity testing, cloning, and microarrays.

Common applications of PCR include:

• Study of gene expression
• Analysis of genetic markers for forensic applications, mapping of hereditary traits, and paternity testing
• Modification of DNA fragments
• DNA analysis of archaeological specimens
• Amplification of gene fragments as an alternative of cloning
• Detection of mutations relevant for tissue typing, inherited diseases or malignant transformation
• Detection of pathogenic microorganisms