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Comment by ajross | Hacker News Reader

Ahem: "Scientists confirm that PARTS OF earliest genetic material came from the stars." You took an already over-sensationalized article title and editted out even the tiny hint of rationality it had left . Shame on you.

From later in the article: "The materials they have found include the molecules uracil and xanthine". This isn't DNA, it's like finding a clay pit and announcing "Our house came from under the earth!".

Sigh...

[EDIT: I see the article title has been fixed to better reflect the source. Many thanks.]

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Even better... "Scientists confirm that parts of earliest genetic material may have come from the stars."

Headlines are awesome. Give it a few more levels of indirection (esciencenews <- hacker news <- bob's blog <- talk around the watercooler) and babies will be dropping from the sky to populate the earth.

It's worse than that. "Scientists confirm that parts of earliest genetic material may have come from the stars".

It really should be "Scientists confirm that simple molecules identical to those which were part of the earliest genetic material can be found on space rocks". Which is only slightly interesting.

It's well known that these sorts of simple hydrocarbons aren't that hard to form -- they would have been forming very frequently on primordial Earth. There is absolutely no reason to suppose that the fact that the occasional uracil molecule also fell out of the sky on a rock would have any effect on the development of life.

I may have been a little over excited on this one, but its still very significant. This is complex organic molecules, direct precursors of DNA components, found in a meteorite. You can downplay this all you want but this is no clay pit vs house :) Sorry again for the sensationalized title; I think I've been exposed too much to Digg, will do better next time.

One of the hardest things to understand about evolution is how quickly organisms change their environment. Before self replicating life forms showed up on earth there was probably a thick soup of complex organic molecules in the land, sea, and air. However, once the most basic of life forms showed up they would quickly consume the abundant resources out there. So while a tiny fraction of early DNA might use components from meteorites there is little reason to think they played a significant role in the evolution of life on earth.

Truthfully, no, it's not all that significant. Here are the relevant wikipedia entries on those molecules:

http://en.wikipedia.org/wiki/Uracil http://en.wikipedia.org/wiki/Xanthine

These are simple molecules. Many organic molecules (including some more complicated than this) have been found in space, either in meteorites or spectrally. This are significant only because they're chemically related to what life ultimately ended up using here on earth (or at least Uracil is, being an RNA pair base -- I have no idea what the Xanthine connection is, honestly).

Really, this isn't all that surprising.

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