Which scientist developed the PCR technique used to copy DNA rapidly?

Kary Mullis developed the polymerase chain reaction, or PCR, used to copy DNA rapidly.

Mullis conceived the key idea in 1983 while working at Cetus Corporation. PCR uses repeated cycles of heating and cooling to separate DNA strands, bind short primers, and extend new strands with a DNA polymerase. Each cycle can approximately double the target sequence, producing millions or billions of copies.

The technique became practical because researchers used a heat-stable polymerase from the bacterium Thermus aquaticus. This enzyme, called Taq polymerase, survives the high temperatures used to separate DNA strands. PCR transformed medical testing, forensic analysis, evolutionary research, and molecular biology.

Mullis shared the 1993 Nobel Prize in Chemistry with Michael Smith. PCR itself is not DNA sequencing: it amplifies a selected region, while sequencing determines the order of its bases.