Dear Readers,
I have been more absent than usual from this blog, which is something I regret. However, the time constraints of preparing for my upcoming qualifying exam necessitate this. I decided to break my strict "no distractions" policy to bring you this bit of info that was emailed to me by a lab mate.
Scientists have discovered DNA components in a meteorite, and they seem to be fairly certain it was made there! You can read the actual NASA press release here, and check out a cool video of one of the scientists explaining the discovery here. The cliff notes version is that, while claims of meteorites containing DNA components have been made before, they may very well have been terrestrial contamination. This seems to be different, because the meteorite also contains similar molecules that are never found in biological matter, which is what would be expected if the DNA molecules (technically nucleobases) were created chemically on the meteorite. This has implications for the evolution of life on earth, and all those big exciting questions about how the search for alien life.
The actual paper (which I admit, I have not had time to read yet) can be found, freely accessible here, in the most recent issue of PNAS.
I know, this might remind you of another fairly recent NASA press release that seemed to tease us with hints of alien life, but I, personally, am much more optimistic about this one.
Thats all for now, wish me luck studying. I promise all sorts of exciting new microbial knowledge to share after I (hopefully) emerge "Docrotral Candidate" from the other side of this exam.
-Heather
- Log in to post comments
No offense, but it bugs me to see headlines like "DNA found in meteors" when it was really just nucleobases. Chemically, that's a loooong way from DNA. The nucleobases would need to be linked to sugars, and the sugars would need to be linked to phosphates, and then the resulting nucleotides would have to be linked together. And even then, you'd still probably only have di- or trinucleotides. Those wouldn't normally be called DNA, any more than a di- or tripeptide (2 or three linked amino acids) would be called a protein.
Hi qetzal,
Thanks for your comment. You are totally correct. I should have been more careful with my wording. I'll edit the post now to be more accurate.
-Heather
Thanks very much!
Nucleobases turning up on meteorites shows that they are much more easily formed than previously thought. This raises the chances they could have been formed on the early Earth, with no need for seeding from space. If nucleobases could have been formed on the early Earth, Occam's razor says we don't need meteorites.
Nucleobases on meteorites has implications for extraterrestrial life, but not for an extraterrestrial origin of life on Earth.
hadi ama adamım Åimdi cekip gidemezsin!
Nucleobases turning up on meteorites shows that they are amuch more easily formed than previously thought. This raises the chances they could have been formed on the early Earth, with no need for seeding from space. If nucleobases could have been formed on the early Earth, Occam's razor says we don't need meteorites.
Nucleobases on meteorites has implications for extraterrestrial life, but not for an extraterrestrial origin of life on Earth