Introduction
DNA (deoxyribonucleic acid) is an essential molecule that can be found in every cell of every organism. DNA carries the genetic instructions used in the growth, development, functioning, and reproduction of all known living organisms and some viruses. Most DNA molecules consist of two strands coiled around each other to form a double helix (like a spiral staircase) \cite{glass}\cite{dna}\cite{wikipedia}.
Currently, DNA isolation it is a routine procedure in molecular biology and forensic analyses. This process extracts DNA molecules from samples like cells or tissues using a combination of physical and chemical methods \cite{Dahm2008}. Nowadays, there are many different commercial kits used for DNA extraction that several laboratories use \cite{Yoshikawa2011}. Every one of our cells contains DNA and extracting it seems like a job for an experienced scientist. But following the next instructions, you would be able to isolate your own DNA using basic kitchen supplies \cite{glass}\cite{dna}.
Materials and methods
To extract your own DNA you need a clean shot glass, your saliva, some milliliters of dish soap, a pinch of table salt, pineapple juice (or contact-lens cleaning solution), ice-cold 120 proof alcohol (like high-proof rum), a drinking straw and a toothpick.
First, you have to spit a lot to fill the shot glass 1/4 full. Add a couple of drops of soap into to the saliva to break (lyse) your cells and mix gently. Now that the cells are broken you need to get rid of other components like proteins. To this end, add a tiny splash of pineapple juice that contains proteases. Proteases break down the proteins and clean the solution. Add a pinch of salt to the saliva solution and mix gently for a minute. Then, carefully add a layer of the overproof rum to fill up the shot glass, which should sit on top of the mixture. To prevent it from mixing too much, add the alcohol gradually using a straw as depicted in figure 1. In this step, the DNA aggregates and clumps together. You should see some cloudy, snot-like white stuff. Finally, use a toothpick to spool up the cloudy DNA that has formed in the shot glass. If you follow the instructions carefully you will isolate your own DNA in just a couple of minutes.