NASA Sequences DNA in Space for the First Time
A NASA astronaut performed the first DNA sequencing in space.
Astronaut Kate Rubins had successfully carried out the experiment on board the International Space Station (ISS) this weekend, using a compact DNA sequencer.
The Biomolecule Sequencer called MinION, which was developed by the UK-based Oxford Nanopore Technologies, was carried by a SpaceX cargo ship to the ISS in July to identify microbes and detect potential causes of illnesses. According to NASA, the device could also possibly detect life elsewhere outside Earth.
DNA sequencing is the process of determining the precise order of the four bases (adenine, guanine, cytosine and thymine) in a DNA molecule of a living organism.
The recent Biomolecule Sequencer experiment proves that DNA sequencing is possible in an orbiting spacecraft. The ability to sequence the DNA of a living organism in microgravity is a "game changer," opening a whole new world of scientific and medical possibilities, NASA said in a press release.
Samples of mouse, virus and bacteria DNA were sent to the space station to test the MinION, the commercially available DNA sequencing device. The MinION works by sending a positive current through nanopores, which are pores embedded in membranes built inside the device, while the fluid containing a DNA sample flows through the device. The nanopores will be partially blocked by individual DNA molecules, which will also change the current in a manner that is unique to the DNA sequence. The changes in the current allow scientists to identify the specific DNA sequence.
Rubins conducted the test aboard the space station while researchers on the ground simultaneously sequenced identical samples. The purpose of the experiment is to make spaceflight conditions, particularly microgravity, the only variables that could account for differences in the results.
For instance, the weightless environment introduced several challenges, such as the air bubbles in the fluid used in the experiment. While on Earth, bubbles rise above the surface of liquid solution and can be removed by centrifuge, bubbles in space are less predictable.
"Onboard sequencing makes it possible for the crew to know what is in their environment at any time," Sarah Castro-Wallace, project manager and NASA microbiologist, said in a statement.
"That allows us on the ground to take appropriate action - do we need to clean this up right away, or will taking antibiotics help or not? We can resupply the station with disinfectants and antibiotics now, but once crews move beyond the station's low Earth orbit, we need to know when to save those precious resources and when to use them."