Scientists have used synthetic bases to double the traditional number of life’s building blocks to eight. The new bases appear to store and transcribe information in the same way as natural DNA, and could in theory also support life.

While “unnatural” bases have been known of since the 1980s, this if the first study to demonstrate that such unnatural bases can recognise and bind to each other, with the helix formed holding its structure functionally.

The synthetic bases were created by tweaking the structures of regular bases, and pair up because the form hydrogen bonds. The new pairs are S and B, and P and Z. The research team then used X-ray diffraction to prove that three different sequences of the synthetic DNA retained the same structure when crystallised.

The ability to convert this synthetic DNA to RNA is an important step, as it means genetic information can be translated into proteins, which in turn govern much of a lifeform’s being.

A number of questions remain around the new DNA, however. It is yet unknown whether synthetic DNA can be replicated by polymerases. Despite this, the new discovery will have a wealth of applications, from better determining signatures of life in other parts of the universe to creating DNA which can do more than store genetic information.