Long missions take a toll on astronauts' brains, necessitating years of recovery.

Prior to recent studies, few people may have guessed that twins would be so useful to the contribution of space research. A new study, however, used data from a pair of identical twins in space to conclude that traveling outside of Earth’s atmosphere could change the genetic makeup of a human being.

Preliminary results for the study released in the Scientific American on January 26th from NASA’s human research program revealed preliminary results regarding identical twins Scott and Mark Kelly. NASA took measurements on the astronaut twins before sending Scott Kelly on his most recent mission. Measurements were also taken during, and after the mission as well.

Between 2015 and 2016, Scott Kelly’s mission required him to spend a total of 340 days in space. Prior to Scott’s mission, Mark Kelly had spent a total of 54 days through 4 missions between the years 2001 and 2011.

Christopher Mason was among the scientists involved in the human research program. “Almost everyone is reporting that we see differences,” stated Mason during the announcement.

Researches claim that their test results suggest that Scott Kelly experienced changes in gene expression and DNA methylation. DNA methylation can cause the activity of a DNA segment to change, but does not change the sequence.

Susan Bailey, a radiation biologist at Colorado State University, also reported changes. She stated that Scott’s telomeres increased in length in comparison to his twin brother’s. Telomeres are areas of receptive nucleotide, and are located at the ends of a chromosome. She added that these results were “exactly the opposite” of were her and her team would have expected.

A geneticist from Johns Hopkins University, Andrew Feinberg, conveyed that everything within the twins’ genes have returned to normal levels since returning from their missions. “What this means is not yet clear,” Feinberg told the Scientific American. Some argue that the rest of the results, even after being reviewed, will not be released. This is because the report could possibly compromise the genetic privacy of both Mark and Scott Kelly.

About Charles Hartwell

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