Adenine and Guanine Detected in Meteorites, Supporting Space-Delivered DNA Building Blocks for Life on Earth

To the point

NASA scientists led by Michael P. Callahan found that DNA-building blocks like adenine and guanine can form in space, with exotic molecules in some meteorites, supporting the idea that pre-made DNA components could have been delivered to early Earth by meteorites or comets to help start life.

NASA Scientific Visualization Studio | Does DNA Have Extraterrestrial Origins?
nasa.gov

NASA Scientific Visualization Studio | Does DNA Have Extraterrestrial Origins?

If terms like adenine and guanine bring back unpleasant memories of Genetics 101 heres one reason to give the words a second thought: A team of scientists has discovered that these and other DNA building blocks can form in outer space and have been deposited on Earths surface by meteorites. To reach this eye-opening conclusion, researchers ground up and analyzed a set of twelve meteorites collected from Antarctica and Australia. Within them, the scientists found a treasure trove of molecules that may have played a key role in allowing early forms of life to form. Adenine, which helps make up the rungs of DNAs spiraling, ladder-like structure, turned up in eleven of the meteorites. Guanine, another key building block of DNA, was present in eight. Two of the twelve meteorites also contained something extraordinary—exotic molecules that are so rare on Earth that they prove the DNA building blocks must have formed in outer space. The discovery lends support to the theory that a kit of pre-made parts from meteorites or a comet might have kick-started life on Earth. Learn more about the breakthrough in the video below. ||