Materials:

Taq (or other) PCR enzyme (5 Units/ul) 　　PCR enzyme reaction buffer 　　Distilled water (nuclease free) 　　DNA to be used as template, such as GAPDH template from Clontech 　　DNA to be used as upstream and downstream primers, such as the 　　corresponding primers set for GAPDH template from Clontech 　　Light mineral oil (nuclease free) 　　dNTP mix (10 mM of each dNTP)

Supplies:

PCR machine and the 600-ul tubes for use in the machine 　　Micropipetter and tips 　　Microcentrifuge with adaptors for 600-ul tubes　　Procedures: 　　Set up the following 2 reactions (final volume of 50 ul each):

Sample Control　　============================================　　distilled water 40 ul 42 ul　　10 X PCR enzyme reaction buffer 5 ul 5 ul　　dNTP mix 1 ul 1 ul　　PCR enzyme 0.25 ul 0.25 ul　　Tab tubes gently to mix and spin for 2 seconds in a 　　microcentrifuge. 　　Add: 　　Sample Control　　=============================================　　downstream primer stock (50 uM) 1 ul 1 ul　　upstream primer stock (50 uM) 1 ul 1 ul　　template (at a concentration of 0.5-2 ng/10 ul) 2 ul 0 ul

Overlay each tube with 1-2 drops (20-40 ul) of mineral oil. 　　Place the tubes in PCR machine. 　　Set up the following profile for 30 cycles: 　　45 seconds at 94 C 　　45 seconds at 60 C

2 minutes at 72 CWithdraw 5 ul from each of the reactions at 15 cycles and store at 　　4 degrees C. Withdraw 5 ul from each of the reactions at 20 cycles and store at 　　4 degrees C. Withdraw 5 ul from each of the reactions at 25 cycles and store at 　　4 degrees C. Store the remaining at 4 degrees C when all 30 cycles are completed. 　　Perform agarose gel electrophoresis (LAB 7) later using the stored reaction mixture.

Results:

After agarose gel electrophoresis, a band of expected size (452 basepairs) should be seen in the "sample" but not in the "control".