Question: How do you extract DNA from

Gemma Marsden answered on 17 Jun 2014:

Hi Kevpopp,

Extracting DNA can be quite easy depending on what you are trying to get DNA from.
It is actually something you can do at home with your parents. You can use food like a handful of peas (or 2 big strawberries) and a few household items (including very cold alcohol).
First of all you need to mush up the food – may be with a blender – this helps us to break down the tissue (think of the cells as house bricks and tissue like a wall – so in effect you are breaking the wall into bricks!)
Then you need to add table salt – this will help to grind up any remaining lumps.
We then need to burst the cells open and can do this by adding washing up liquid mixed with water (ask an adult to dilute 20 ml of washing up liquid with 60 ml of water). The washing up liquid is doing the same thing here that is does to fat or grease when you are washing up.
This will release the cell contents and we need to remove the bits we don’t want. To do this, get a coffee filter or sieve and tip your cell mush into the filter and let it drip through.
Once that has happened (it may take some time!), remove the filter and very slowly pour the cold alcohol down the side of the glass. If you do this slow enough you will 2 different layers one containing the alcohol and one containing the washing up liquid and water. You should see white fluffy stuff where the 2 layers meet – that is DNA!