How to Extract DNA From Human Cheek Cells
From your Biology Guide

Lab method for extracting DNA from human cheek cells.

Difficulty Level: Easy    Time Required: 15 minutes

1. Gather together sodium chloride, liquid soap, 2 glass beakers, bottled and distilled water, 2 test tubes, test tube stoppers, glass rod, a plastic cup and rubbing alcohol.
2. Place 8 grams of sodium chloride in one of the beakers and dissolve with 92 milliliters of distilled water.
3. In a second beaker, combine 25 milliliters of liquid soap with 75 milliliters of distilled water.
4. Pour 1 milliliter of the sodium chloride solution into a large test tube.
5. Pour 10 milliliters of the bottled water into a plastic cup and swirl the water in your mouth for 30 seconds.
6. Spit the water back into the cup and pour the contents into the test tube containing the sodium chloride solution.
7. Add 1 milliliter of liquid soap to the test tube.
8. Cover the top of the test tube with a stopper and gently mix the contents by turning the test tube upside down and right side up.
9. Add 5 milliliters of the rubbing alcohol to the test tube making sure to pour it at an angle down the side of the test tube.
10. Wait for about 5 minutes and watch as the DNA floats to the surface.
11. Pour 1 milliliter of alcohol into the second test tube.
12. Use the glass rod to remove the DNA from the first test tube by twirling the rod in a circular motion.
13. Place the DNA into the second test tube containing the alcohol.
    

Tips:

1. If more DNA is desired, repeat the procedure making sure to wash your mouth more vigorously in step 5.

Related Information:

• Genetics
  

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