The aim of the recent exercise by the astronauts was to examine how DNA repair mechanisms operate in microgravity. To examine this, scientists on-board the International Space Station (ISS) snipped at strands of a fungus’s genetic code in a number of places in order to mimic radiation damage. Such research feeds into the planned human mission to Mars.
For the experiment, the astronauts used CRISPR gene editing technology. CRISPR is an acronym for ‘clustered regularly-interspaced short palindromic repeats’. The technique refers to a type of biological cut-and-paste technology whereby molecular scissors are deployed to initiate changes to deoxyribonucleic acid (DNA). There are many potential applications of this form of biotechnology, which extend to correcting genetic defects, treating and preventing the spread of diseases and improving crops. However, the focus of the ISS study was to examine the impact of space travel.
The process involved inducing breaks into DNA strands of the yeast Saccharomyces cerevisiae, in order to imitate potential radiation damage to the organism. The strain of yeast has been instrumental in winemaking, baking, and brewing since ancient times (hence the common name – brewer’s yeast).
According to researcher Emily Gleason of miniPCR Bio (the research center which designed the DNA lab aboard the space station): “The damage actually happens on the space station and the analysis also happens in space…We want to understand if DNA repair methods are different in space than on Earth.”
Such research is important since the Earth’s atmosphere shields humans from cosmic radiation that can damage DNA. However, astronauts in space have no such protection, and, in the context of the planned mission to Mars, this puts them at risk. Concerns relate to long-term risk for cancer, degenerative diseases and central nervous system problems.
With the study, by examining the molecular structure of the yeast’s DNA before and after the simulated damage-repair cycle., this enables researchers to observe the changes in the molecular structure of the fungus. This will provide a valuable insight into whether the DNA repair mechanism introduces any significant genetic errors.
