A new study demonstrated that human DNA can survive a trip through space and re-entry into Earth's atmosphere without losing the ability to pass on genetic information.
Researchers attached double-stranded DNA molecules to the outside of the payload section of a rocket using pipettes, the University of Zurich reported. After the rocket re-entered Earth's atmosphere, the DNA was found to still be present on the original application points. To the researcher's surprise, this DNA was also still able to transfer genetic information to bacteria and connective tissue.
"This study provides experimental evidence that the DNA's genetic information is essentially capable of surviving the extreme conditions of space and the re-entry into Earth's dense atmosphere," said study head Professor Oliver Ullrich from the University of Zurich's Institute of Anatomy.
The experiment, dubbed DARE (DNA atmospheric re-entry experiment), was spawned from the TEXUS-49 mission, which worked to determine how gravity influenced gene expression in zero gravity inside the rocket. Researchers wondered if the outside of the spacecraft could also be used to facilitate experimentation.
The experiment was thrown together at the last minute, and was originally meant to check the stability of biomarkers after re-entry into Earth's atmosphere.
"We were completely surprised to find so much intact and functionally active DNA," said UZH scientist Cora Thiel.
The findings suggest that DNA from outer space could enter Earth's atmosphere in vessels such as the dust from meteorites, about 100 tons of which hit the planet on a daily basis. The findings could have implications on the search for extraterrestrial life.
"The results show that it is by no means unlikely that, despite all the safety precautions, space ships could also carry terrestrial DNA to their landing site. We need to have this under control in the search for extraterrestrial life," Ullrich concluded.
The findings were published Nov. 26 in the journal PLOS ONE.
