concept

Xeno nucleic acid (XNA)

A molecule that carries genetic information like DNA or RNA but is built on a different backbone - swapping the sugar or spine for a component Earth life does not use. XNA proves that our particular twisted ladder is not the only workable choice: information can be stored and copied on several chemistries. This feeds both synthetic biology and the hunt for "weird" life - an organism using XNA would be invisible to tools that only know how to read the familiar backbone.