Have you ever tried putting a left-hand glove on your right hand? It doesn’t fit quite right! Some tiny building blocks of life are like gloves. They come in left-handed and right-handed forms. This special property is called chirality (pronounced ky-RAL-ih-tee). Even though the two forms look almost like mirror images, they are not exactly the same.
Here is the great mystery: when scientists make these molecules, they often get a mixture of left-handed and right-handed forms. But living things mostly use only one form for certain important building blocks. For example, life uses mostly left-handed amino acids to build proteins. How did life choose one hand over the other when life first began?
Scientists have discovered ways a tiny difference can grow into something much bigger. Imagine one team starts with just one extra player. That player helps the team grow, and soon the team becomes much bigger than the other. Some molecules can do something similar: a few molecules of one handedness can help produce more molecules with the same handedness. This is called amplification.
These discoveries help scientists understand how a tiny, perhaps accidental, difference could have grown over time until life mostly used one hand instead of the other. We still don’t know exactly how this happened on early Earth, but chirality may hold an important clue to one of the biggest mysteries of life!
What this is not. Education only. Stories on cells.com are not medical advice. cells.com does not diagnose, treat, prescribe, run laboratory tests, or ship kits.
Simon Ng is the founder of cells.com. He has spent more than a decade on biotech finance executive teams, including at Quark Pharmaceuticals and Adverum Biosciences, and holds an MBA.