I'm no chemistry expert and I can only recount what details I remember of the conversation, but apparently this new discovery grew out of NASA's "Deep Impact" mission to study the composition of comets. Scientists have previously tried to get DNA to spontaneously appear by recreating in the lab the conditions that it first formed, but with no success. According to this revolutionary theory, the reason for this failure is simple -- they lack the correct "pattern" needed for it to be created.
Specifically, they found a kind of carbon that can form in layers, kind of like a crystal, with each layer offset slightly from the previous one in a kind of lattice. Imagine if you laid a deck of cards down on a table, and then twisted them slightly into a helix-like shape and you'd get the general idea. Significantly, the thickness of these carbon layers directly corresponds to the thickness of each slight "twist" in a strand of RNA.
It turns out that the individual building blocks of RNA -- adenine, guanine, cytosine, uracil, and thymine -- are capable of bonding to this layered form of carbon when exposed to ultraviolet radiation. Infact, they're predisposed to do so due to the particular arrangement of the carbon atoms. What is needed after that is some basic substance to bond the RNA together to form a kind of "sheet" on the carbon material. They believe this came from formaldehyde which, combined with the kind of simple material available from common volcanism, would bond to the building blocks of RNA, and then slough off the carbon material in question.
Next thing you know, you have strands of RNA floating around in the primordial soup. Some of these strands would fold upon themselves and bond, forming DNA. Over time, formaldehyde, the bonding material, would get more chemically sophisticated, creating the kind of chemical bond that we observe today in DNA.
So, there ya go. A new, groundbreaking theory to the secret to live itself, simple and elegant enough to quite possibly be true. We all got our start in life as some congealed scum that grew on a chunk of carbon... perhaps a bit of stardust, so to speak. The big breakthrough came in May 2004, but expect a paper on it to be released in approximately 3-4 months with all the details.
I just found a big piece of the puzzle I've been trying to figure out as to exactly what this molecular biologist told me.
I was just referred to this article over at Salon. This is exactly what the person in question was talking about. Also, read this article, and search through these links.
As it says in the Salon articke:
"somebody's got to come up with a mechanism that bridges the gap between a planet covered with a random stew of interesting molecules and the incredible complexity of RNA. . . Has Platts solved this problem? Hazen would like to think so, but he's far too cautious to say anything definitive. . . It's well known that much of the organic material from outer space to reach the prebiotic Earth came in the form of flat, sturdy molecules called polycyclic aromatic hydrocarbons, or PAHs. Platts began to see how PAHs could have been energized by solar radiation and self-assembled into stacks in the ancient ocean. Small, flat amino-acid molecules would begin to stick to the outside of this "stack of plates," and the whole array would begin to look "for all the world like the information-rich genetic sequence of DNA or RNA." This would have been nothing more than an intriguing, left-field notion if not for the fact that the space between these PAH layers is 0.34 billionths of a meter, which just happens to be precisely the distance between the ladder-like rungs of a DNA or RNA molecule. Somehow -- and Platts doesn't propose exactly how -- this interesting but haphazard assemblage of molecules became a coherent vector of biochemical information, broke free of its PAH host and folded over on itself to become a "true pre-RNA genetic molecule."
Well, it seems like he's filled out his theory to explain how this primitive RNA broke free from the PAH host. Specifically, the formaldehyde solution. Turns out that noressa and I met Nick Platts while soaking in a hot tub at Kiva last night. Seems like an appropriate place to meet him, really.