DNA of gemini astronauts

Gemini astronauts and the impact of space on health

Julia Korovsky, XX2 century, based on Nature News: Astronaut twin study hints at stress of space travel

At a meeting of researchers of the Human Research Program at NASA, preliminary results of the Twin Study project were presented. This study was devoted to the impact of long-term space flights on health. The program was attended by two twin astronauts - Scott (Scott Kelly, left) and Mark Kelly (Mark Kelly, with a mustache :). Analyses of the biological material of the twins showed that during the time spent in orbit, one of them changed the expression of genes and other biological indicators.

A picture from the NASA press release How Stressful Will a Trip to Mars Be on the Human Body? We Now Have a Peek Into What the NASA Twins Study Will Reveal – VM.

"In November 2012, shortly after Scott Kelly was selected for a one-year space flight, he asked: will my brother do anything interesting on Earth? We realized that this is a unique opportunity to conduct a series of studies, because we have one twin in space and the other on earth," says Craig Kundrot, deputy head of the Human Studies Program. Twin astronauts have almost identical genomes and similar life experiences, so NASA experts decided to take samples of biological material from the brothers before and after the end of the flight and compare them. In addition to blood and urine samples, they were interested in intestinal flora, physiology, behavior and thinking.

On January 26, in Galveston, Texas, scientists presented preliminary results of the study. "Almost everyone reports seeing differences," says Christopher Mason, a geneticist at the Weill Cornell Medical School, one of the members of the scientific group Cornell University (Cornell University). "The data is so fresh that some of it still comes from sequencers," Mason says.

Now researchers face a difficult task – to understand which changes are associated with space flight, and which appeared as a result of natural processes. And since there are only two twins, it is impossible to draw conclusions about people in general from the data obtained. But this does not mean that the experiment was useless: during the Twin Study, NASA specialists managed to conduct a very detailed analysis of gene expression. "The most important thing is to show that we can do this," explains Andrew Feinberg, a member of the scientific group, "I don't think people realized that studying the genomics of astronauts in space is so easy."

During the 2015-2016 mission, Scott Kelly spent 340 days in space. His brother Mark flew shuttles for 54 days from 2001 to 2011. Analysis of the length of the telomeres – the end sections of the twin chromosomes showed that during the last mission, Scott's telomeres became longer than his brother's. "This is the complete opposite of what we expected," admits Susan Bailey, a specialist in radiation biology at Colorado State University in Fort Collins (Colorado State University). However, the scientists were not mistaken, their results were confirmed by another laboratory. When Scott Kelly returned to Earth, his telomeres quickly returned to the pre-flight level. NASA experts intend to find out what's the matter. They have started a separate study with the participation of other astronauts, it is expected that this experiment will be completed in 2018.

For the year at Scott's amount of methylated DNA decreased, while Mark's, on the contrary, increased. After the mission was completed, the indicators of both men returned to the previous level. What this means is not yet clear to scientists. In addition, the Mason research group reports that the twins' gene expression has changed. On Earth, this happens often and, as a rule, is associated with the restructuring of environmental conditions, for example, with a shift in the day mode. But Scott's deviations exceeded the norm.

We will not be waiting for articles with the results of the study soon, and probably some of the data will not be made publicly available at all. Now the Kelly brothers will have to review all the information in order to prevent confidential information from being published.

DNA methylation is the modification of a DNA molecule without changing the nucleotide sequence itself. It consists in attaching a methyl group to a specific DNA site. The methylated nucleotide can then be oxidized by special enzymes, which ultimately leads to its demethylation. Methylation DNA is considered to be mainly inherent in eukaryotes. In humans, about 1% of genomic DNA is methylated.

Portal "Eternal youth" http://vechnayamolodost.ru  31.01.2017