"NASA and the other researchers collaborating on these studies expect to announce more comprehensive results on the twins studies this summer". Mark remained on Earth, while Scott was on the International Space Station. "His gene expression - the transcribing and translation of genes, not the genes themselves - was what actually changed during his year on the space station", added Miriam Kramer in Mashable. But now, the science site is correcting its report with a March 16 mea culpa headlined, "We Were Totally Wrong About That Scott Kelly Space Genes Story".
NASA has learned astronaut Scott Kelly and his identical twin- astronaut Mark Kelly- are no longer genetically the same.
"Mark and Scott Kelly are still identical twins; Scott's DNA did not fundamentally change", NASA said. Researchers discovered that while 93 percent of Scott Kelly's genes returned to normal after landing, the remaining 7 percent did not. Overall, 7 percent of his genes witnessed changes, as compared to his twin. Kelly's transformation suggests longer-term alterations related to at least five biological pathways and functions. Gene expression refers to how active a particular piece of DNA is.
"It's also not surprising that a lot of these expression levels are returning to normal as Scott recalibrates to Earth's environment", she said. "So that would make a major change in how we think about exploring the solar system, exploring space, and a change in understanding who we are and what we can do as explorers". But the genes in the study, not a flawless match anymore.
What they found is that spaceflight creates oxygen-deprivation stress, increased inflammation throughout the body, and facilitated dramatic nutrient shifts that affect genes directly.
The Kelly brothers have almost identical genomes, allowing for an unprecedented look at the physical effects of long-term spaceflight. "If a study were done of identical twins where one ISN'T spending time in space, we'd still see differences in expression levels and telomere length", Avey said.
Another interesting finding concerned what some call the "space gene", which was alluded to in 2017.
"The last time we posted anything was at the end of January, and it was just confirmation that some results from a year ago had been validated", he said. First, there was a significant increase in average length while he was in space, and then there was a decrease in length within about 48 hours of his landing on Earth that stabilized to almost preflight levels. All of these findings are being integrated and summarized by the research teams; researchers are also evaluating the possible impact that these findings will have on future space travel beyond low Earth orbit.