High-power laser hints at origin of RNA

The Hebrew Bible says that God made humans from dust,* but maybe it was a slurry of clay and water. That is a tentative conclusion you might draw from an experiment that used a (very) high-powered laser beam to zap a suspension of clay in an aqueous solution of formamide, a very simple organic compound. The result has been reported in the press, but there is a somewhat more-precise article in Science magazine. (You may find the abstract of the original article here and the supporting information here. I did not get access to the full article.)

In a nutshell, a team at the J. Heyrovský Institute of Physical Chemistry in Prague used a laser that can produce up to 1 kJ in a 300 ps pulse,** irradiated the suspension, and produced adenine, cytosine, guanine, and uracil, which are the bases of the RNA molecule. And apparently not a drop of thymine, one of the bases of DNA. The experiment is supposed to simulate the bombardment of the early Earth by comets and presumably supports the hypothesis that an RNA world came first.

* Actually, Job, Isaiah, Psalms, and I imagine elsewhere say clay, as in, “We are the clay, and you are our potter.” (Don’t get excited; I consider the fact to have no significance whatsoever.)

** I am a laser physicist and wrote my thesis on laser-produced plasmas, so you must forgive me for somewhat stressing the laser, which to this day gives me a certain amount of pulse envy.