adapted by Roxane Bonner
Laboratory of Molecular Systematics and Evolution
University of Arizona
Vigorously swish 15 mL of Gatorade in your mouth
for 30 seconds. Chew on your cheeks while swishing so you get
as many cells as possible. Remember: more cells = more DNA!!!
Spit the Gatorade back into your cup, then pour
it into a new 15 mL plastic tube. Mark your tube and lid with
your initials.
Find a partner and make sure your tubes each
have the same volume. Add more Gatorade if necessary to make the
volumes equal. Place your tubes opposite each other in a centrifuge.
Spin the tubes on high for 3-5 minutes to collect cells at the
bottom of the tube.
Pour the liquid into a waste container.
Repeat steps #1-4. Pour the Gatorade/Spit from
your second mouthwash into the tube with the cells from your first
mouthwash.
Add 2.0 mL of Lysis Buffer to the cell pellet.
Mix by carefully flicking the tube.
OPTIONAL . Add 50
(l of Proteinase K (see teacher). Flick the tube to break up the
cell pellet.
Incubate the cells at 65-70 C for atleast one
hour, preferably overnight. Before proceeding, the solution should
be clear and the cells should not be visible.
Add 1.0 mL of 5M NaCl.
Mix well, then centrifuge for 10 minutes on high
speed.
Transfer the liquid into a new 15 mL tube. Do
not let the stuff on the bottom fall into the new tube. If necessary,
use a clean pipet to transfer only the liquid.
Add 4 mL of cold 95% ethanol to the liquid in
the new tube.
Mix well by rocking the tube gently back and
forth until the DNA becomes visible. It should look like fine
white fibers or lint.
