Artificial Life created in Lab,Playing God's role.

Scientists have succeeded in creating the first organism with “alien” DNA. In normal DNA, which can be found within the genes of every organism , the twin strands of the double helix are bonded together with four bases, known as T, G, A, and C. In this new organism, the researchers added two new bases, X and Y, creating a new form of DNA that (as far as we know) has never occurred after billions of years of evolution on Earth or elsewhere in the universe. Remarkably, the semi-synthetic alien organism continued to reproduce normally, preserving the new alien DNA during reproduction. In the future, this breakthrough should allow for the creation of highly customized organisms — bacteria, animals, humans — that behave in weird and wonderful ways that mundane four-base DNA would never allow.

This landmark study, 15 years in the making, was carried out by scientists at the Scripps Research Institute and published in Nature today [doi:10.1038/nature13314 - "A semi-synthetic organism with an expanded genetic alphabet"]. In normal DNA, two separate strands are entwined in a double helix. These strands are connected together via four different bases, adenine (A), thymine (T), cytosine (C), and guanine (G). A always bonds with T, and C always bonds with G, creating a fairly simple “language” of base pairs — ATCGAAATGCC, etc. Combine a few dozen base pairs together in a long strand of DNA and you then have a gene, which tells the organism how to produce a certain protein. If you know the sequence of letters down one strand of the helix, you always know what other letter is. This “complementarity” is the fundamental reason why a DNA helix can be split down the middle, and then have the other half perfectly recreated. There, I just explained in about 150 words two of the most vital processes to all life that we know of.

The full Nature write-up is worth reading if you want the nitty-gritty details, but here’s the short version. First, the scientists genetically engineered an e. coli bacterium to allow the new chemicals (d5SICS and dNaM) through the cell membrane. Then they inserted a DNA plasmid (a small loop of DNA) that contained a single XY base pair into the bacterium. As long as the new chemicals were available, the bacterium continued to reproduce normally, copying and passing on the new DNA, alien plasmid and all. In the study, this process seems to have carried on flawlessly for almost a week.

Source: Nature Magazine.