Salt reveals invisible code

A mysterious matter is hiding deep inside your cells, determining your destiny, and still, you have never seen it. But with a few simple ingredients from your kitchen cupboards, you can now reveal the DNA molecules and hold them in your hand.

Your body includes thousands of billions of copies of your DNA. The vital matter, that exists in almost all your cells, holds the genetic code that controls your body’s development and maintenance. The indispensable molecules are normally crumpled up and dissolved in water, so we cannot see them. But a simple experiment can extract the DNA from its hiding place inside cells and make it visible to us. Spit is a good source of DNA, as it contains thousands of cells from the inside of the mouth, and the cells can easily be opened up with a little washing- up liquid. Lemon juice acid halts enzymes that would otherwise cut up the cell’s molecules, ensuring that the DNA remains intact. But the mysterious matter is still not visible. DNA is electrically charged, and this very quality makes sure that it can be dissolved in water, which is also partially charged. In a dissolution of salt and ethanol, the molecules unfold, and the salt ions neutralise their charges. When this happens, the DNA clots, appearing as white threads in the liquid. You can use a swab to capture the threads and touch the matter that makes you who you are.