Yesterday in my lab session at university, we extracted our own DNA (for sequencing, to see how things like forensic analysis and paternity/maternity tests work). But while extracting DNA sounds super sciencey and complicated (and impressive - when I was telling my friends about how I was extracting and sequencing DNA this week their reaction was always to go “wow! Awesome!”), it is actually something that you can do yourself with a blender, salt, pineapple juice and alcohol.
1. Figure out what you want to use as a source of DNA. You can get your DNA from anything living - but you might want to use fruit, vegetables or parts of a plant for this experiment, because you’ll need to blend up the cells and so using animals would be just a little bit unethical(okay, so I said above that I extracted my own DNA, and I did do this without chopping myself up, but this is a little bit harder - we took cheek swabs and then had to centrifuge everything for about a million hours, so if you don’t have your own bench-top centrifuge, then use strawberries or something instead).
2. Blend it up so it becomes a paste (blend on high for 15 seconds). This breaks open (lyses) many of the cells. Also add a pinch of salt.
3. Add detergent. This will lyse the cells further and also break open the cell’s nucleus, which is where the DNA lives.
4. This step is not necessary if you just want to extract and look at DNA, and not do any further measurements with it (like spectrophotometry). But if you have it available, add some pineapple juice to your mixture. Pineapple juice contains an enzyme called bromelain that eats proteins. You need to add this to remove proteins from your solution - because cells are also full of proteins, and when you break open your cell, a whole bunch of proteins will come flowing out. And if you remove the proteins, the stuff you extract will be more “pure” DNA.
5. Add vodka/rubbing alcohol/anything with a high ethanol content. Carefully add the alcohol to the top of your mix. DNA does not dissolve in alcohol, so if you add enough it will “precipitate” out of the solution. Stringy white shapes should appear in your solution. This is strands of DNA! (Yes, you can see it!) You can then put a straw or skewer into the solution, twirl it and pull it out. The DNA you have extracted will look a lot like mucous or snot ;)
And that’s how you extract DNA at home! You don’t even need any fancy lab equipment. Pretty easy, huh?