# Austronaut genetics
**URL:** https://boards.straightdope.com/t/austronaut-genetics/507993
**Category:** Factual Questions
**Created:** [August 28, 2009, 2:50am UTC](https://boards.straightdope.com/t/austronaut-genetics/507993 "2009-08-28T02:50:51Z")
**Posts on this page:** 18
**Page:** 2
### Author:  [@kenobi\_65](https://boards.straightdope.com/u/kenobi_65)
#### Post date: [March 15, 2018, 5:25pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/21 "2018-03-15T17:25:07Z")
> [@Irishman](#):
>
> “remains changed”… Isn’t that an oxymoron? Someone flubbed that sentence.
Yeah, it’s not like his DNA has some “revert to prior save point” setting. 😛
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### Author:  [@Riemann](https://boards.straightdope.com/u/Riemann)
#### Post date: [March 15, 2018, 5:49pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/22 "2018-03-15T17:49:03Z")
> [@Irishman](#):
>
> That article starts with a line that reads strangely: “Astronaut Scott Kelly’s DNA was altered during his year in space, and seven percent of his genetic code remains changed, according to research conducted by NASA.”
>
> “remains changed”… Isn’t that an oxymoron? Someone flubbed that sentence.
I don’t see why it’s an oxymoron, no. If something changes and then doesn’t change back, it remains changed.
The article is poorly written, because his DNA sequence was not altered, just gene expression (as Darren Garrison noted). Kelly’s pattern of gene expression changed in response to the unusual environment on ISS, and it has not completely changed back since he return to earth.
The background reason that this may be interesting is that changes in gene expression are mediated by numerous mechanisms, some of which are less transient than others. There is (wildly overhyped) evidence that under some circumstances, some epigenetic marks that mediate gene expression may even be passed on to offspring.
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### Author:  [@markn\_1](https://boards.straightdope.com/u/markn_1)
#### Post date: [March 15, 2018, 8:43pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/23 "2018-03-15T20:43:11Z")
Yeah, when I saw that statement that seven percent of his DNA had changed, I thought I was reading the National Enquirer or something. What happened, has he changed into a cat?
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### Author:  [@Shodan](https://boards.straightdope.com/u/Shodan)
#### Post date: [March 15, 2018, 8:54pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/24 "2018-03-15T20:54:56Z")
Can he now turn invisible, stretch long distances, burst into flames, or be covered in orange pottery shards and be incredibly strong?
Regards,
Shodan
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### Author:  [@Chronos](https://boards.straightdope.com/u/Chronos)
#### Post date: [March 15, 2018, 9:02pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/25 "2018-03-15T21:02:21Z")
Yeah, just like he could before he went into space. You don’t mean to tell me that you can’t do those things, do you?
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### Author:  [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)
#### Post date: [March 16, 2018, 2:49pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/26 "2018-03-16T14:49:09Z")
In the Sci-Fi novel “Rendezvous with RAMA” it is stated that, due to solar radiation, genetic damage was a certainty, and astronauts must be sterilized. If you want children, “arrangements” must be made prior to committing to your career. :rolleyes:
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### Author:  [@OldGuy](https://boards.straightdope.com/u/OldGuy)
#### Post date: [March 16, 2018, 3:08pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/27 "2018-03-16T15:08:51Z")
> [@Chronos](#):
>
> Yeah, just like he could before he went into space. You don’t mean to tell me that you can’t do those things, do you?
No Shodan is a conservative. He’ll never change.
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### Author:  [@kenobi\_65](https://boards.straightdope.com/u/kenobi_65)
#### Post date: [March 16, 2018, 3:25pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/28 "2018-03-16T15:25:31Z")
> [@Shodan](#):
>
> Can he now turn invisible, stretch long distances, burst into flames, or be covered in orange pottery shards and be incredibly strong?
_claps_
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### Author:  [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)
#### Post date: [March 16, 2018, 7:08pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/29 "2018-03-16T19:08:37Z")
[Here](https://www.washingtonpost.com/news/speaking-of-science/wp/2018/03/16/the-truth-about-astronaut-scott-kellys-viral-space-genes/?utm_term=.2412c2d37eb3) is a nice “hold your horses, popular press” article.
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### Author:  [@Irishman](https://boards.straightdope.com/u/Irishman)
#### Post date: [March 16, 2018, 7:15pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/30 "2018-03-16T19:15:26Z")
> [@Riemann](#):
>
> The article is poorly written, because his DNA sequence was not altered, just gene expression (as Darren Garrison noted). Kelly’s pattern of gene expression changed in response to the unusual environment on ISS, and it has not completely changed back since he return to earth.
Now that makes sense. The sentence in the article doesn’t.
> [@Enola\_Straight](#):
>
> In the Sci-Fi novel “Rendezvous with RAMA” it is stated that, due to solar radiation, genetic damage was a certainty, and astronauts must be sterilized. If you want children, “arrangements” must be made prior to committing to your career. :rolleyes:
Asimov may have been positing conditions that aren’t met by the current US program, such as long duration missions away from Earth orbit. He might also have been overhyping the risk for dramatic effect. Also, he might not have considered early-pregnancy genetic screening a viable route to diagnosing and treating embryos for hazardous genetic defects.
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### Author:  [@Jasmine](https://boards.straightdope.com/u/Jasmine)
#### Post date: [March 16, 2018, 7:22pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/31 "2018-03-16T19:22:55Z")
> [@wierdaaron](#):
>
> I’ve heard that an astronaut on a space walk (like, say, repairing Hubble) receives something like 1,000 times the cosmic radiation we do every second.
Perhaps, but consider the fact that an astronaut spends but a few minutes in space out of his entire lifetime, and only a handful of human beings have ever even done that. We simply don’t have enough data on the subject to draw any conclusions.
Two vital factors in any valid study are sample size and the duration of the study. This particular situation is sorely lacking in both.
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### Author:  [@Riemann](https://boards.straightdope.com/u/Riemann)
#### Post date: [March 16, 2018, 7:35pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/32 "2018-03-16T19:35:14Z")
> [@Jasmine](#):
>
> We simply don’t have enough data on the subject to draw any conclusions.
There’s actually a Wiki article on it. We know the dose quite accurately, but as you say there’s considerable uncertainly about the relative effect of cosmic radiation vs (say) X-rays or nuclear reactors/weapons where we have a lot more data.
> **[Effects of ionizing radiation in spaceflight](https://en.wikipedia.org/wiki/Spaceflight_radiation_carcinogenesis)**
>
> Astronauts are exposed to approximately 72 millisieverts (mSv) while on six-month-duration missions to the International Space Station (ISS). Longer 3-year missions to Mars, however, have the potential to expose astronauts to radiation in excess of 1,000 mSv. Without the protection provided by Earth's magnetic field, the rate of exposure is dramatically increased. \[failed verification\] The risk of cancer caused by ionizing radiation is well documented at radiation doses beginning at 100 mSv Relat...
And, as has been pointed out already, the uncertainty concerns the probability of disease and death, not the probability of mutating into some kind of transformed human. Just as with germline mutations in evolution, mutations that have any significant effect are overwhelmingly deleterious.
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### Author:  [@Chronos](https://boards.straightdope.com/u/Chronos)
#### Post date: [March 17, 2018, 3:34am UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/33 "2018-03-17T03:34:05Z")
> [@](#):
>
> Quoth **Irishman** :
>
> Asimov may have been positing conditions…
Nitpick: Clarke.
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### Author:  [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)
#### Post date: [April 10, 2018, 7:30pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/34 "2018-04-10T19:30:23Z")
[Bumpity](https://www.bloomberg.com/view/articles/2018-04-10/nasa-mutant-astronauts-and-the-space-gene-that-wasn-t).
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### Author:  [@lazybratsche](https://boards.straightdope.com/u/lazybratsche)
#### Post date: [April 10, 2018, 7:43pm UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/35 "2018-04-10T19:43:53Z")
Whelp, despite the good intentions of the author in trying to untangle and correct some atrocious science reporting, this whopper got through:
> [@](#):
>
> The original NASA press release doesn’t define “space gene,” but introduces it as if the reader is supposed to know what it means. Mason said he meant for the term to apply to **all the genes** affected by space flight – 7 percent of **Kelly’s approximately 60,000** …
Bolding mine. Clearly, the “space genes” are the 40,000 new extra genes that Kelly picked up during his time on the ISS! I assume that means he’s a xenomorph now.
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### Author:  [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)
#### Post date: [April 12, 2018, 2:52am UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/36 "2018-04-12T02:52:20Z")
> [@markn\_1](#):
>
> Yeah, when I saw that statement that seven percent of his DNA had changed, I thought I was reading the National Enquirer or something. What happened, has he changed into a cat?
Only 7% changed would have to be something lots more human-like than a cat.
Humans share something like 98-99% of their DNA with the great apes.
Cats and mice have about 10% different gene sequences from humans. Doge are further away, with about 16% difference. Cattle are higher, about 20% difference. You have to get into the plants, and exotic ones, to find things that are genetically unlike humans. Even plants like the banana are still 60% common gene sequences with humans.
(And he wouldn’t “turn into a cat” – at most, such a DNA change would affect his offspring. And even tht only if they were still fertile with his wife, or she had similar genetic changes.)
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### Author:  [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)
#### Post date: [April 12, 2018, 10:59am UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/37 "2018-04-12T10:59:13Z")
That depends on [what level of granularity you are looking at it](http://www.caltech.edu/news/humans-and-chimps-have-95-percent-dna-compatibility-not-985-percent-research-shows-614). Say you have 2 genes that are 100 base pairs long–one gene is identical between the two species and one has two base pair differences. Depending on the level you are “thinking at”, the two genes represent either a 50% difference or a 1% difference. So the ambiguous phrasing “7% of DNA changed” can mean either “7% of all genes have a difference” or “7% of all base-pairs are different.”
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### Author:  [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)
#### Post date: [April 13, 2018, 5:04am UTC](https://boards.straightdope.com/t/austronaut-genetics/507993/38 "2018-04-13T05:04:11Z")
> [@Shodan](#):
>
> Can he now turn invisible, stretch long distances, burst into flames, or be covered in orange pottery shards and be incredibly strong?
That stuff’s easy. But can he break a hundred million in his opening weekend?
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