I’ve occasionally said with exaggerated admiring boastfulness ‘My plant geneticist daughter can extract DNA…’ without really having any understanding about what on earth this might involve. Of course I’m an avid fan of any tv program where DNA matching helps solve serious crimes 🙂 but really, I’ve no idea. I remember when it was ‘discovered’ way back in my youth; and I’m always interested when DNA sequencing, mapping, genomes and all that kind of thing are mentioned in media reports showing how science is advancing to discover more about our world, or help the world’s medical problems. But as I said, I really had no idea more than a general one about ‘DNA’.
It turns out, though, that using simple ingredients and procedures, any of us lay people can extract some DNA from food stuff in our own domestic laboratory, the kitchen. This I know because under my daughter’s supervised guidance, I recently did this in her kitchen. Not difficult, certainly not dangerous, not glamorous really – not so mysterious after all, she says confidently.
Frozen plant matter (frozen strawberries and frozen spinach) in plastic ziploc bags.
Add some canned pineapple juice for the enzymes it contains that the DNA molecules will attach to. As it all thaw pummel and squash the strawberries and spinach to as close to a sludge as possible. This breaks down the cell walls so that the DNA can be retrieved once the final ingredient is added.
Place each sludge in a glass so you can see what happens when grain alcohol is added.
The clear layer of alcohol above each sludge gradually becomes clouded with what looks like cotton wool, the speed and amount of this varying plant to plant.
This cloudy cotton wool stuff is the DNA ! You can scoop it out by fork or spoon, use it on ice cream maybe … (or take it to your scientific instruments that light up with leds and go ping) – but for me that was the end of the experiment/demo. And I don’t think I want to take this any further – my curiosity has been satisfied for the moment at least.
They say no education is wasted, and I’m not sure what I’m going to do with this knowledge, but it may come in handy some day. Thanks teach!