Are we children of the stars?

The DNA was undoubtedly one of the greatest discoveries of science, not from the 19th century, when it was isolated for the first time by Friedrich Miesche at the University of Tübingen, Germany, but from the entire history of science. And it is that, although it would still take more than a century and a half until the human being was able to interpret it in its entirety, he was the first to observe the instruction book that defines each form of life.

As we already recalled when speaking of the last great milestone in human genome research, The nitrogenous base of the DNA molecule can be of four typeseach of them identified with a letter, adenine (A), cytosine (C), guanine (G) and thymine (T). In the case of RNA, the composition is similar, except that thymine is replaced by uracil., which is also a nucleotide. Thus, if we take into account DNA and RNA, we can speak of five hydrogenated bases: adenine, cytosine, guanine, thymine and uracil.

The theory that life on our planet has its origin in space comes from ancient. Now, at this point it is convenient to clarify that I am not referring to theories of spaceships that came tens of millions of years ago to bring samples to Earth or anything like that. And no, I don’t mean that the pyramids of Egypt are the work of aliens, although I admit that I had a dwarf time with Stargate, and it is even likely that I will see it again soon.

No, I’m talking about theories that suggest that the basis of DNA and, therefore, of life as we know it, could have its origin in space, and they could have arrived on Earth as unexpected passengers in meteorites that collided with our planet. And there are reasons to think that it is possible, although it is true that, in the face of them, there are still reasons to think that it is not so, and that DNA has its unique origin in the third large stone from the Sun.

And it is that, until now, the analysis of some meteorites that fell on Earth millions of years ago revealed traces of adenine, guanine and uracil, three of the nucleobases that we mentioned earlier. These elements were detected with classical techniques, of limited scope. However, and according to Science News, a new analysis method developed by geochemist Yasuhiro Oba of Hokkaido University in Sapporo, Japan, would have also allowed to find cytosine and thyminethus completing the pool of DNA and RNA.

Even more, some of the samples analyzed would contain the five hydrogenated basesso that if it could be confirmed that they were already carrying them before colliding with the Earth, the finding would be very revealing, since it would allow to support, with a more solid basis, that the origin of DNA, and therefore of life as it is. as we know it, has its origin in space, and not necessarily on our planet.

Do the DNA bases really come from space?

Now, there is a very, very important nuance, and it is precisely the one that I raised at the beginning of the previous paragraph, that is, the need to confirm that the nucleobases were already in the samples before they reached our planet. The three samples analyzed reached our planet in the years 1950, 1969 and 2000, so the possibility that the five elements reached them when they were already on the Earth’s surface is very, very real. Thus, with the current samples, there is no way to determine its origin.

Does this mean that we are back to the beginning? No, far from it. For now, the most important point is that we already have the necessary technology to be able to detect the presence of the five nucleobases of DNA and RNA in this type of sample, something that was not possible until the work of Yasuhiro Oba was completed. And this breakthrough comes at the right time.

Anow, of course, what we need are samples of meteorites that have not come into contact with our planetand the good news is that, as I indicated before, this is the right time, since in 2020 the Japanese space mission Hayabusa extracted a piece of rock from the surface of an asteroid called Ryugu and brought it to Earth, and at the time NASA is developing a similar mission with the asteroid Bennu, whose sample is expected to reach our planet in September 2023.

If the scientific community has the possibility of analyzing these samples with the system developed by Oba, and the result shows the presence of adenine, cytosine, guanine, thymine and uracil, and therefore of the DNA base, we will come closer than ever to that of being children of the stars And, although this does not reveal to us if there is more life in the universe, it will tell us that the base of life inhabits it for millions of years. And, as Moby told us back in 2002, And no one can stop us now, ‘Cause we are all made of stars.