How to Extract DNA

1. Chop the onion into small pieces and place inside the blender container.

2. Measure out 200 mls of the water. Pour this into a glass and add one level teaspoon of salt. Microwave the salty water for one minute (High) then stir well.

3. Add enough of the salty water to just cover the onion.

4. Blend the mixture for about 10 seconds.

5. Pour the onion-salt-water mixture through the strainer and collect the liquid in a glass. The DNA from the onion is in this liquid.

6. Measure out 50 mls of the onion liquid and pour it into a glass.

7. Add 2 teaspoons of dishwashing detergent to the glass containing the 50mls of onion liquid. Stir very gently.

8. Measure out 100 mls of methylated spirits. Slowly add the methylated spirits to the glass containing the onion-detergent mixture.

9. Now wait for the DNA to appear! The DNA is white, rising up from the bottom of the glass. Be patient as it may take a few minutes to appear. (If no DNA appears after 5 minutes, try again using suggestions from What went wrong? )

DNA rising from the bottom of the cup to the top

Clean up the kitchen. The methylated spirits and DNA from your experiment should be poured down the sink.