It has been over 50 years since the discovery of the double-stranded nature of DNA, and over that half-century and more we have learned a lot about deoxyribonucleic acid, from the fact that it organizes into a double-stranded double helix all the way to having sequenced the entire DNA of humans and a range of other organisms. Now, according to a paper published in the Journal of the American Chemical Society, a team in Japan has created the world's first DNA strand made from artificial bases.

As information storage systems go, DNA is not bad. Just four different bases (adenine, thymine, guanine, and cytosine) are all that's needed to code for 20 different amino acids, using three base codons (e.g. AUG). In fact, the four-base, triplet codon system has the potential to be able to store information for more than just 20 amino acids; there are 64 potential combinations, so several amino acids have multiple codons, along with three stop codons that tell the cellular machinery involved that the sequence is done.

Along the way, people have looked at DNA and thought that it ought to be possible to use DNA to store nonbiological data. Better still, it can pack that information into far smaller packages than is possible with solid state memory or even the densest hard drive platters. There have also been experiments that use DNA sequences to perform parallel processing, as we covered last year.

But we needn't be limited to the four complementary bases, and that's just what has been shown by a Japanese team, who have published details of their creation of an artificial DNA strand. All the components of their DNA product are nonnatural, yet they spontaneously form right-handed duplexes with the corresponding opposite base, and these bonds have very similar properties to those of natural DNA.

The hope is that this artificial DNA could have a range of applications in the real world, from the aforementioned DNA computing proposals, along with using DNA to store data, to using it in nanotech settings. Artificial DNA has similar physical properties to common-or-garden DNA without being degraded by enzymes such as DNase (which is found everywhere), a factor that would make it quite useful for any kind of biomedical setting.

JACS, 2008. DOI: 10.1021/ja801058h