NASA Twin Study: How Space Changes Our Bodies

NASA astronaut Scott Kelly spent almost one year, orbiting

Earth aboard the International Space Station.

While his identical twin brother, Mark Kelly, who is

also an astronaut, spent that same time, here

on Earth; this gave NASA the unique oppurtunity

to study the impact of long term space travel

on human biology.

To find out more, we talked to one

of the study's lead authors, Doctor Francine

Garrett-Bakelman.

You know it's rare to have twins.

[chuckles]

And it's even rarer to have twins

that are both astronauts, right, I mean

that's unheard of.

NASA and really Scott Kelly came up

with this concept that it would be really great

to do this research project and study the effects

of long term space flight, on not only physiological

parameters that NASA really studies heavily

and has been for many many decades,

but to really expand that, on to include molecular

information and some additional parameters

that might be important for long term space travel,

using his brother as a control, as a reference

because they're genetically identical.

[Robbie] Scott Kelly collected biological samples

like blood and urine while he was

in space and at the same time, his brother Mark Kelly was

on Earth, collecting the exact same kinds

of samples.

So describe to me one of the more high stake scenarios

that you were involved in personally, receiving a high

priority sample, having to process it, you know, right

then, are you up first like are you up at

like 2:00 in the morning, what's going on?

[Francine] If you recall, he landed around midnight.

Two, there were actually two specimen's coming

in; one was collected on the space station, right

before he left and came down with him.

The second one was planned to be collected

from him when he got to the Johnson Space Center, you know

I got these two specimen's at like two o'clock

in the morning, 2:30 in the morning and I was

in the lab to around eight, nine o'clock

in the morning, working continuously, you know

and that was, that was a big responsibility.

[chuckling]

Cause if I would've made a mistake

that night, the results would have been different,

but that was really, I would say for me

that was kind of a highlight experience because

in science you don't routinely get

to experience something like that.

Right, if you're working with something

in the laboratory, usually you can get more material

not always, but usually.

and it's not like you get one or two tubes and it's your one

shot, right, you can't reproduce this.

No you can't, like when is the next time you're going

to have, when's the next time you're going to get twins.

That's just not going to work, right?

[chuckling]

So that was kind of unique, I have

to say.

Let's talk about, the biggest take aways

from what you found, cause you were looking at a lot

of stuff, right, you're looking at epigentic, you're

looking at genetic expression, you're

also looking at microbiome stuff, you're looking at

cognitive function, so you covered a lot

of territory, let's talk about what the biggest take aways

were.

Preliminarily, there's a strong suggestion

that human biology can be maintained at the cellular level.

Not just physiological level and that will really facilitate

long term travel and safety for astronauts long term.

I would say the next most important findings were the

telomere caps.

Telomere's the caps of the chromosomes got longer

in space flight, that was unexpected.

The telomere's are really these caps

that sit on the edges of chromosomes and they protect

our genetic material from becoming damaged, and every

test we did basically showed the same result

that the telomere's got longer

with flight and within two days

of him coming back, they shrunk down

to where they were, the next finding which I was involved

with was gene expression view.

There was a lot of gene changes and inflammation and stress

responses, we expected to see, I would have been shocked

if they weren't.

Gene expression refers to whether a section

of your DNA, is turned on or off.

Some genes control for fixed rates

like eye color,

but others like the ones that help regulate your metabolism

are turning off and on all the time.

I mean the thing people need to remember right is

like gene expression changes in response

to everything.

Every day, every hour, right, every day, every hour

and so, it would have been shocking

if we saw nothing, he had gene expression changes

that were correlated with the time

that he was in space, and after he came back the vast

majority of those greater than 90 percent came back

to where they were before flight

by the six month mark, after he returned.

Who knows, if we would have measure

that a year late, like a year after return, maybe

that number would be much higher.

95, 96, 97, two years later maybe everything

is back to normal, we just don't know the answer to that.

[Robbie] We already know that space travel

is rough on humans, for instance it can interfere

with the movement of fluids in the body

because there is no gravity, they can accumulate in the head

and this can have a number of side effects, up

to 40 percent of astronauts have lasting vision problems,

but this study is the beginning

of understanding more about what happens

to the human body in space.

It points the way towards, questions

that you know, NASA or other space agencies might ask

about, what kind of protective measures can we take

when we're sending people to space.

We already know that in microgravity, you lose muscle

mass, you lose bone density, and they've developed sort

of exercise regiments to counteract that right?

[Francine] Right.

But like maybe there's a pill we can take

in the future that can help with some

of these.

Absolutely.

Absolutely, time will tell.

What if any, are the implications

of these findings for longer durations

of space missions, people talk about a mission

to Mars, right, and a fly by mission

to Mars, not even touching down.

Going around, coming home, that's 500 days.

I think it gives us some perspective and direction

of the areas in molecular biology

that should be focused on and should be studied further,

but the first step to this will be

to reproduce the same study and additional astronauts

who will be on International Space Station

for a year and then as the space agency start traveling

further out, the same studies will have

to be repeated, to see if these things are reproducible,

because it could be that this is an end of one, and

it's an end of one, and we will never see this again.

Right, it could be that, it could be

that Scott is just particularly resistant

to the ravages of space right?

One thing to keep in mind though is

that when the astronauts are in the International Space

Station, they have a very strict diet, and a

very strict exercise regiment and

so, it could be that what we detected was actually a

consequence of this lifestyle change.

They might be living healthier lives

in space than Mark was on Earth.

[Francine] And he is a Caucasian male,

if it's an African American male, woman, who knows

if these will be reproducible, and

so we have to be careful with what we think and what we say

because it's really hard to tell, what the implications are,

but I think at the end of the day, the study was informative

it gives insight to the potential molecular mechanisms

that might be affected by space flight and they

can give direction, for counter measures

to be considered and additional studies

to be done in the future.

Hey thank you again, so much for joining us

Thanks for the opportunity to chat today.