Life on Earth may have been 'sent' from space

DNA is inherently made up of four major building blocks of life (nucleobases), called adenine (A), thymine (T), cytosine (C) and guanine (G). Meanwhile, the "DNA's brother" molecule, RNA, also uses A, C, and G, but swaps thymine for uracil (U).

 These nucleobases are found in DNA and RNA in meteorites that have come to Earth

Scientists have long hypothesized about the origin of these masses, wondering if meteorites were the "train" that brought them to Earth. But so far, they have only found A and G in space rocks. And T, C and U are still unknowns. 

However, in a recent discovery, scientists from Hokkaido University, Japan claim that they have found the "complete" of all 5 nucleobases - which exist in two forms as purines (with the nucleus made from a hexagonal molecule, fused with a pentagonal molecule) and pyramid (a structure made of only one hexagonal molecule).

To come to this conclusion, the scientists analyzed samples from three carbon-rich meteorites, including the Murchison, Murray and Tagish meteorites. In which, 3 missing nucleobases, T, C and U, were detected even at very low levels of a few parts per billion, but in sufficient concentrations at levels comparable to those found in laboratory reproduction experiments.

According to the scientists, these nucleobases are found in DNA and RNA in meteorites that have come to Earth. Therefore, the hypothesis that life on Earth may have been "sent" from space is probably completely valid.

"The presence of five major nucleobases in meteorites may have contributed to genetic functions, even before life began on Earth," said Yasuhiro Oba, the study's lead author and one of the researchers. astrophysicist at Hokkaido University, Japan.

From this result, Oba and colleagues even suggest that these "genetic letters" may have existed since before the formation of the Solar System, and that they could actually act as "trains". ", bringing life to every corner of the universe.

The project's researchers detailed their findings in the journal Nature Communications, published April 26.