Astronauts' DNA mutation awakens Sleeping cells in space
4hw.com.cn: Recently, there was a heated discussion on the gene mutation of NASA astronauts according to law. The astronaut stayed in space for 340 days. After inspection, there was a gene mutation in his body. Maybe the space environment awakened the sleeping cells in his body. Let's see the details below.
NASA astronaut Scott Kelly spent 340 days on the international space station. Scientists are curious whether his physical condition has changed? So he found mark Kelly, his twin brother with the same gene, and compared it. It was found that Scott's' immune system and DNA repair function 'had mutations. From the perspective of genetic genes, it was a permanent damage that could not be recovered.
According to the research report in the journal Science, three years after Scott, 55, returned to earth, scientists carried out a systemic examination of him and found that during his stay in space, his carotid artery and retina became thicker, his weight became lighter, his intestinal microorganisms increased, and his cognitive ability decreased. However, most of these symptoms gradually disappeared six months after returning to earth, Only 8.7% of the changes in genes have not been recovered.
Scott said that the first few days back to earth were very uncomfortable. He had no vitality for a long time and was very tired. 'I thought I had the flu'.
Rachael Seidler, a cognitive neuroscientist at the University of Florida, said, "these gene mutations do not pose a direct risk to astronauts, but they do not rule out increasing their risk of cancer in the future."
Susan Bailey, a cancer biologist at Colorado State University, said that there is a part called 'telomere' at the end of human chromosome, which usually shortens with age. Radiation, pollution, pressure and other factors may cause it to shorten faster, but strangely, after Scott went to space, the telomere did not shorten, but longer than before, In other words, 'his cells are younger than before', which is likely to be 'space awakens some sleeping cells in his body'.
The researchers pointed out that there are five possibilities for Scott gene mutation, including the impact of space radiation and zero gravity environment on physiology. Because Scott's space station was just under the Van Allen radiation belt of high-energy charged particles, and the amount of radiation is 48 times that of the earth, body cells will always be busy repairing radiation damage, This mutation occurs.