Was DNA created in outer space?

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>>Mike Callahan: background music My name is Mike Callahan. I'm a research physical scientist in the Astrobiology Analytical Laboratory at NASA Goddard Space Flight Center. We've a discovered a variety of nuclear bases and nuclear based analogs and meteorites. What a nuclear base is is it's a small molecule that's found in DNA and RNA and these molecules are essential for all of life. And so results show that these molecules are extraterrestrial in origin and they're products of a chemical reaction occurring on the meteorite. We believe that these nuclear bases and meteorites are extraterrestrial based on three reasons and the first is that we find nuclear based analogs in meteorites. What a nuclear based analog is is that it is a molecule that is structurally similar to the nuclear bases you find in biology but it's different in that these structures are actually either rare or even absent on earth. The second reason is that in addition to looking at meteorite samples we also study terrestrial samples. So these meteorites are collected mostly in Antarctica and one that's very famous called Murchison was collected in Australia. So we have soil samples from that Murchison area in Australia and we've also had, we were lucky enough to get an ice sample from Antarctica where some of these meteorites were collected. And so when we look at these soil and ice samples in a laboratory we don't see the same distribution of nuclear bases. And with these nuclear based analogs we don't see them at all in these terrestrial samples. The third reason why we think this nuclear base was extraterrestrial in meteorites is that in the laboratory we study reactions of hydrogen cyanide and when we extract the products from these hydrogen cyanide reactions we also get nuclear bases and we actually get a similar suite of nuclear bases to what's found in a meteorite. And so when we saw that we were really excited because we were thinking well hydrogen cyanide is dispersed everywhere in the interstellar medium and it's likely to have some sort of chemical reaction of a meteorite. And so when we saw that that really convinced us a lot that we are seeing something from a chemical reaction rather than some sort of biological contamination coming into the meteorite. So this has implications for the origin of life on earth. We know that meteorites contain amino acids which are the building blocks in your proteins and now from our research we can show that nuclear basis, which are the building blocks of your genetic material, and DNA and RNA are also found in meteorites. And so these things together could have ceded in early earth with these really important molecules that could have built up to the larger molecules you see today that are essential for biology.

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