The polymerase chain reaction and pathology practice

Pathology practice is increasingly augmented with molecular tests for improved diagnostics and patient management. The polymerase chain reaction (PCR) is foremost amongst these techniques. This review explains the principles of PCR and the methodological factors that contribute to a successful assay. Key PCR technique variations, such as reverse transcription (RT)-PCR and quantitative real-time (q) PCR, are described and an overview is provided of how PCR products are analysed. The review includes examples of PCR usage in clinical practice for the detection of infectious and genetic diseases, for tumour diagnostics and in molecular forensic applications such as specimen identity confirmation.