Tardigrades are pretty much impossible to kill. No, seriously — the tiny organisms also known as water bears or mossy piglets can survive the following environments: the vacuum of outer space, near absolute zero, boiling temperatures, pressures six times greater than the deepest ocean, several years’ worth of dehydration, and radiation lethal to pretty much every other animal on Earth. Scientists now know what gives Tardigrades that latter quality — and it could be a boon to making deep space travel for human beings possible.
Cosmic radiation is still an incredible obstacle to safe interstellar travel. Our understanding of how radiation in space affects the human body has always been murky at best, and the first astronauts shot into space are now suffering from that lack of understanding.
There is no shortage of ideas for what could be employed to protect future astronauts bound for Mars and beyond — including genetic engineering. Which brings us to tardigrades.
In a new study published in Nature Communications, a team of researchers University of Tokyo presented a genetic analysis of Ramazzottius variornatus, which is thought to be among the toughest tardigrade species, and identified the protein responsible for keeping tardigrade DNA safe from radiation. Dsup, short for “Damage suppressor,” basically works by enveloping DNA and covering it from harmful agents without affecting the normal activity of genetic material.
Okay, great for tardigrades. What does this have to do with humans and space, you ask?
Well, the team decided to genetically engineer human kidney cells grown in a lab culture to produce their own version of Dsup, and found that damage to those cells induced by X-rays was reduced by up to 50 percent.
If a human being were genetically modified to produce Dsup throughout most or almost all their tissue and organs, it would go a long way towards protecting them from the cosmic rays she would be inundated by in space.
This wouldn’t be foolproof — humans producing Dsup, in its current state, would still experience harm via cosmic rays, and genetic manipulation of humans is more than a ways away, even with emerging technologies like CRISPR.
Still, this is more encouraging than nearly every other biological solution pitched before it. Humans might still be able to get to Mars relatively safely, but if we plan to venture to worlds further out, optimizing our genes to prepare for such an endeavor would be pretty effective.