Polymerase Chain Reaction

Qai Gordon and Maddy Marchetti

What is Polymerase Chain Reaction?

• Polymerase Chain Reaction (PCR) is a process that amplifies small pieces of DNA to create multiple copies of that DNA sequence

• Also called DNA amplification

Applications of PCR

• To s tudy pat terns o f gene express ion• To f ind the presence o f genet ic d isease

mutat ions• To prov ide therapy for cancer pat ients• To prov ide more substant ia l ev idence in

c r ime scenes• To ana lyze the DNA of anc ient organ isms

DNA sample is obtained and denatured by heating it to 98°C

Step 1

Step 2

• DNA sample is cooled to 60°C• Primers are annealed (bonded) to each strand–Primers: short strands of DNA that set up the

starting sequence for the DNA synthesis

Step 3

• DNA polymerase binds to the primers and synthesizes the target DNA sequence with free nucleotides

Results of PCR

• After one cycle, two copies of the original target sequence exist

• If steps 1-3 are repeated multiple times, the DNA replicates at an exponential rate

Thermal CyclerLoading tray: where prepared samples are placed in tiny tubes

Temperature Control: heating and refrigeration mechanisms inside the machine to change the temperature quickly

Controls: ways to control the machine and start and stop the PCR process

Animation

• http://www.youtube.com/watch?v=_YgXcJ4n-kQ