Polymerase Chain Reaction (PCR)

Excerpt

The polymerase chain reaction (PCR) is a frequently utilized laboratory nucleic acid amplification technique that uses Taq polymerase, a thermostable DNA polymerase isolated from Thermus aquaticus, to synthesize DNA following thermal denaturation and primer annealing. Kary Mullis introduced PCR in 1985 and was later granted the Nobel Prize in Chemistry for this contribution. PCR enables precise detection and analysis of amplified DNA and has become a cornerstone of biomolecular research.

This technique targets specific DNA fragments within a sample and amplifies them through repeated cycles of denaturation, annealing, and extension. Taq polymerase is favored for its thermostability, which preserves enzymatic function despite repeated exposure to high temperatures. PCR is considered the gold standard for diagnosing bacterial and viral infections and for screening genetic disorders because of its high sensitivity.