Space sciences and astronomy
29 Nov 2021
DNA of future deep-space explorers could become more ‘error prone’ in microgravity
By Mischa Dijkstra, Frontiers science writer During parabolic flight to simulate weightless conditions in space, researchers show for the first time that a DNA polymerase enzyme derived from bacteria makes 10-140% more errors while copying DNA in microgravity. Combined with the known greater rate of DNA damage from space radiation, this inaccuracy of DNA replication is likely to pose a threat to the health of future astronauts on long missions. On 22 May 2019, scientists from Queen’s University boarded a modified Falcon 20 aircraft at Ottawa airport. Scheduled was a ‘vomit comet’ flight, where the plane repeatedly climbs to 8km in a steep parabola, alternating with a descent in freefall. During freefall, at a rate of over 3.3km in 20 seconds, only gravity but no lift, thrust, or drag work on the plane, resulting in weightlessness. The scientists’ mission under these difficult conditions was to test whether the enzymes that copy DNA are as accurate under weightlessness as under earthbound conditions. This question is of paramount importance for future space exploration, as the health of astronauts will depend on accurate DNA replication during cell division. “So-called DNA polymerases are essential enzymes that copy and repair DNA. Inevitably, they aren’t perfect: […]