NASA, not media, is to blame for the Twin Study 7% DNA change misunderstanding

In case the title threw you out of the loop, let me pull you back in. In 2015, NASA sent Scott Kelly to the International Space Station while his twin brother, Mark, stayed on the ground. When Scott came back, NASA ran a bunch of tests on them to see how space affects human body. Some of the findings were published a few weeks ago. Among the findings, one caught the eyes of media who ran stories like:  Astronaut Scott Kelly now has different DNA to his identical twin brother after spending just a year in space (Daily Mail), Astronaut’s DNA no longer matches identical twin’s after time in space, NASA finds (Channel 3), Astronaut Scott Kelly’s genes show long-term changes after a year in space (NBC), Astronaut Scott Kelly is no longer an identical twin: How a year in space altered his DNA (Fox News), Scott Kelly Spent a Year in Space and Now His DNA Is Different From His Identical Twin’s (Time),  Nasa astronaut twins Scott and Mark Kelly no longer genetically identical after space trip (Telegraph), Astronaut’s DNA changes after spending year in space when compared to identical twin bother (The Independent), Astronaut Scott Kelly’s DNA No Longer Matches Identical Twin’s After a Year in Space (People), NASA study: Astronaut’s DNA no longer identical to his identical twin’s after year in space (The Hill), NASA astronaut who spent a year in space now has different DNA from his twin (Yahoo News), Scott Kelly: NASA Twins Study Confirms Astronaut’s DNA Actually Changed in Space (Newsweek), If you go into space for a long time, you come back a genetically different person (Quartz), Space can change your DNA, we just learned, (Salon), NASA Confirms Scott Kelly’s Genes Have Been Altered By Space Travel (Tech Times), even ScienceAlert 😦 ran Scott Kelly’s DNA Is No Longer Identical to His Twin’s After a Year in Space.  And dozens and dozens more….

Even the astronauts themselves said their DNA is different and they are no longer twins:

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But, dear Scott & Mark Kelly, rest assured that despite these titles and their afferent stories, you two share the same DNA, still & forever. You are still identical twins until one of you changes species. Because that is what 7% alteration in human DNA means: you’re not human anymore.

So what gives?

Here is the root of all this misunderstanding:

“Another interesting finding concerned what some call the “space gene”, which was alluded to in 2017. Researchers now know that 93% of Scott’s genes returned to normal after landing. However, the remaining 7% point to possible longer term changes in genes related to his immune system, DNA repair, bone formation networks, hypoxia, and hypercapnia.” (excerpt from NASA’s press release on the Twin Study on Jan 31, 2018 (see reference).

If I wouldn’t know any better I too would think that yes, the genes were the ones who have changed, such is NASA’s verbiage. As a matter of actual fact, it is the gene expression which changed. Remember that DNA makes RNA and RNA makes protein? That’s the central dogma of molecular biology. A sequence of DNA that codes for a protein is called a gene. Those sequences do not change. But when to make a protein, how much protein, in what way, where to make this protein, which subtly different kinds of protein to make (alternative splicing), when not to make that protein, etc. is called the expression of that gene. And any of these aspects of gene expression are controlled or influenced by a whole variety of factors, some of these factors being environmental and as drastic as going to space or as insignificant as going to bed.

Some more scientifically inclined writers understood that the word “expression” was conspicuously missing from the above-mentioned paragraph and either ran clarification titles like After A Year In Space, NASA Astronaut’s Gene Expression Has Changed. Possibly Forever. (Huffington Post) or up-front rebukes like No, space did not permanently alter 7 percent of Scott Kelly’s DNA (The Verge) or No, Scott Kelly’s Year in Space Didn’t Mutate His DNA (National Geographic).

Now, I’d love, LOVE, I tell you, to jump to the throat of the media on this one so I can smugly show how superior my meager blog is when it comes to accuracy. But, I have to admit, this time is NASA’s fault. Although it is not NASA’s job to teach the central dogma of molecular biology to the media, they are, nonetheless, responsible for their own press releases. In this case, Monica Edwards and Laurie Abadie from NASA Human Research Strategic Communications did a booboo, in the words of the Sit-Com character Sheldon Cooper. Luckily for these two employees, the editor Timothy Gushanas published this little treat yesterday, right at the top of the press release:

“Editor’s note: NASA issued the following statement updating this article on March 15, 2018:

Mark and Scott Kelly are still identical twins; Scott’s DNA did not fundamentally change. What researchers did observe are changes in gene expression, which is how your body reacts to your environment. This likely is within the range for humans under stress, such as mountain climbing or SCUBA diving.

The change related to only 7 percent of the gene expression that changed during spaceflight that had not returned to preflight after six months on Earth. This change of gene expression is very minimal.  We are at the beginning of our understanding of how spaceflight affects the molecular level of the human body. NASA and the other researchers collaborating on these studies expect to announce more comprehensive results on the twins studies this summer.”

Good for you for rectifying your mistake, NASA! And good for you too the few media outlets that corrected their story like CNN who changed their title from Astronaut’s DNA no longer same as his identical twin, NASA finds to Astronaut’s gene expression no longer same as his identical twin, NASA finds.

But, seriously, NASA, what’s up with you guys keep screwing up molecular biology stuff?! Remember the arsenic-loving bacteria debacle? That paper is still not retracted  and that press release is still up on your website! Ntz, ntz, for shame… NASA, you need better understanding of basic science and/or better #Scicomm in your press releases. Hiring? I’m offering!

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REFERENCE: NASA. Edwards, M.  & Abadie, L. (Jan. 31, 2018). NASA Twins Study Confirms Preliminary Findings, Ed. Timothy Gushanas, retrieved on March 14,15, & 16, 2018. Address:

By Neuronicus, 16 March 2018

P.S. Sometimes is a pain to be obsessed with accuracy (cue in smallest violins). For example, I cannot stop myself from adding something just to be scrupulously correct. Since the day they were conceived, identical twins’ DNAs are starting to diverge. There are all sorts of things that do change the actual sequence of DNA. DNA can be damaged by radiation or exposure to some chemicals. Other changes are simply due to random mutations. So no twins are exactly identical, but the changes are so minuscule, nowhere near 1%, let alone 7%, that it is safe to say that their DNA is identical.

P.P.S. With all this hullabaloo about the 7% DNA change everybody glossed over and even I forgot to mention the one finding that is truly weird: the elongation of telomeres for Scott, the one that was in space. Telomeres are interesting things, they are repetitive sequences  of DNA (TTAGGG/AATCCC) at the end of the chromosomes that are repeated thousands of times. The telomere’s job is to protect the end of the chromosomes. Every time a cell divides the DNA copying machinery cannot copy the last bits of the chromosome (blame it on physics or chemistry, one of them things) and so some of it is lost. So evolution came up with a solution: telomeres, bits of unusable DNA that can be safely ignored and left behind. Or so we think at the moment. The length of telomeres has been implicated in some curious things, like cancer and life-span (immortality thoughts, anyone?). The most common finding is the shortening of telomeres associated with stress, but Scott’s were elongated, so that’s the first weird thing. I didn’t even know you can elongate them in living humans. But wait, there is more: NASA said that “the majority of those telomeres shortened within two days of Scott’s return to Earth”.  Now that is the second oddest thing! If I would be NASA that’s where I would put my money on, not on the gene expression patterns.

Arnica and a scientist’s frustrations

angry-1372523 - CopyWhen you’re the only scientist in the family you get asked the weirdest things. Actually, I’m not the only one, but the other one is a chemist and he’s mostly asked about astrophysics stuff, so he doesn’t really count, because I am the one who gets asked about rare diseases and medication side-effects and food advice. Never mind that I am a neuroscientist and I have professed repeatedly and quite loudly my minimum knowledge of everything from the neck down, all eyes turn to me when the new arthritis medication or the unexpected side-effects of that heart drug are being brought up. But, curiously, if I dare speak about brain stuff I get the looks that a thing the cat just dragged in gets. I guess everybody is an expert on how the brain works on account of having and using one, apparently. Everybody, but the actual neuroscience expert whose input on brain and behavior is to be tolerated and taken with a grain of salt at best, but whose opinion on stomach distress is of the utmost importance and must be listened to reverentially in utter silence [eyes roll].

So this is the background on which the following question was sprung on me: “Is arnica good for eczema?”. As always, being caught unawares by the sheer diversity of interests and afflictions my family and friends can have, I mumbled something about I don’t know what arnica is and said I will look it up.

This is an account of how I looked it up and what conclusions I arrived to or how a scientist tries to figure something out completely out of his or her field. First thing I did was to go on Wikipedia. Hold your horses, it was not about scientific information but for a first clarification step: is it a chemical, a drug, an insect, a plant maybe? I used to encourage my students to also use Wikipedia when they don’t have a clue what a word/concept/thing is. Kind of like a dictionary or a paper encyclopedia, if you will. To have a starting point. As a matter of fact Wikipedia is an online encyclopedia, right? Anyway, I found out that Arnica is a plant genus out of which one species, Arnica Montana, seems to be popular.

Then I went to the library. Luckily for me, the library can be accessed online from the comfort of my home and in my favorite pajamas in the incarnation of PubMed or Medline as it used to be affectionately called. It is the US National Library of Medicine maintained by the National Institutes of Health, a wonderful repository of scholarly papers (yeah, Google Scholar to PubMed is like the babbling of a two-year old to the Shakespearian sonnets; Google also has an agenda, which you won’t find on PubMed). Useful tip: when you look for a paper that is behind a paywall in Nature or Elsevier Journals or elsewhere, check the PubMed too because very few people seem to know that there is an obscure and incredibly helpful law saying that research paid by the US taxpayers should be available to the US taxpayer. A very sensible law passed only a few years ago that has the delightful effect of having FREE full text access to papers after a certain amount of months from publishing (look for the PMC icon in the upper right corner).

I searched for “arnica” and got almost 400 results. I sorted by “most recent”. The third hit was a review. I skimmed it and seemed to talk a lot about healing in homeopathy, at which point, naturally, I got a gloomy foreboding. But I persevered because one data point does not a trend make. Meaning that you need more than a paper – or a handful – to form an informed opinion. This line of thinking has been rewarded by the hit No. 14 in the search which had an interesting title in the sense that it was the first to hint to a mechanism through which this plant was having some effects. Mechanisms are important, they allow you to differentiate speculation from findings, so I always prefer papers that try to answer a “How?” question as opposed to the other kinds; whys are almost always speculative as they have a whiff of post factum rationalizations, whats are curious observations but, more often than not, a myriad factors can account for them, whens are an interesting hybrid between the whats and the hows – all interesting reads but for different purposes. Here is a hint: you want to publish in Nature or Science? Design an experiment that answers all the questions. Gone are the days when answering one question was enough to publish…

Digressions aside, the paper I am covering today sounds like a mechanism paper. Marzotto et al. (2016) cultured a particular line of human cells in a Petri dish destined to test the healing powers of Arnica montana. The experimental design seems simple enough: the control culture gets nothing and the experimental culture gets Arnica montana. Then, the authors check to see if there are differences in gene expressions between the two groups.

The authors applied different doses of Arnica montana to the cultures to see if the effects are dose-dependant. The doses used were… wait, bear with me, I’m not familiar with the system, it’s not metric. In the Methods, the authors say

Arnica m. was produced by Boiron Laboratoires (Lyon, France) according to the French Homeopathic pharmacopoeia and provided as a first centesimal dilution (Arnica m. 1c) of the hydroalcoholic extract (Mother Tincture, MT) in 30% ethanol/distilled water”.

Wait, what?! Centesimal… centesimal… wasn’t that the nothing-in-it scale from the pseudoscientific bull called homeopathy? Maybe I’m wrong, maybe there are some other uses for it and becomes clear later:

Arnica m. 1c was used to prepare the second centesimal dilution (Arnica m. 2c) by adding 50μl of 1c solution to 4.95ml of distilled ultra-pure water. Therefore, 2c corresponds to 10−4 of the MT”.

Holy Mother of God, this is worse than gibberish; this is voluntary misdirection, crap wrapped up in glitter, medieval tinkering sold as state-of-the-art 21st century science. Speaking of state-of-the-art, the authors submit their “doses” to a liquid chromatograph, a thin layer chromatograph, a double-beam spectrophotometer, a nanoparticle tracking analysis (?!) for what purposes I cannot fathom. On, no, I can: to sound science-y. To give credibility for the incredulous. To make money.

At which point I stopped reading the ridiculous nonsense and took a closer look at the authors and got hit with this:

“Competing Interests: The authors have declared that no competing interests exist. This study was funded by Boiron Laboratoires Lyon with a research agreement in partnership with University of Verona. There are no patents, products in development or marketed products to declare. This does not alter our adherence to all the PLOS ONE policies on sharing data and materials, as detailed online in the guide for authors.”

No competing interests?? The biggest manufacturer of homeopathic crap in the world pays you to see if their product works and you have no competing interest? Maybe no other competing interests. There were some comments and replies to this paper after that, but it is all inconsequential because once you have faulty methods your results are irrelevant. Besides, the comments are from the same University, could be some internal feuding.

PLoS One, what have you done? You’re a peer-reviewed open access journal! What “peers” reviewed this paper and gave their ok for publication? Since when is homeopathy science?! What am I going to find that you publish next? Astrology? For shame… Give me that editor’s job because I am certain I can do better.

To wrap it up and tell you why I am so mad. The homeopathic scale system, that centesimal gibberish, is just that: gibberish. It is impossible to replicate this experiment without the product marketed by Boiron because nobody knows how much of the plant is in the dose, which parts of the plant, what kind of extract, or what concentration. So it’s like me handing you my special potion and telling you it makes warts disappear because it has parsley in it. But I don’t tell you my recipe, how much, if there anything else besides parsley in it, if I used the roots or only the leaves or anything. Now that, my friends, it’s not science, because science is REPLICABLE. Make no mistake: homeopathy is not science. Just like the rest of alternative medicine, homeopathy is a ruthless and dangerous business that is in sore need of lawmakers’ attention, like FDA or USDA. And for those who think this is a small paper, totally harmless, no impact, let me tell you that this paper had over 20,000 views.

I would have oh so much more to rant on. But enough. Rant over.

Oh, not yet. Lastly, I checked a few other papers about arnica and my answer to the eczema question is: “It’s possible but no, I don’t think so. I don’t know really, I couldn’t find any serious study about it and I gave up looking after I found a lot of homeopathic red flags”. The answer I will give my family member? “Not the product you have, no. Go to the doctors, the ones with MDs after their name and do what they tell you. In addition, I, the one with a PhD after my name, will tell you this for free because you’re family: rub the contents of this bottle only once a day – no more! – on the affected area and you will start seeing improvements in three days. Do not use elsewhere, it’s quite potent!” Because placebo works and at least my water vial is poison free.

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Reference: Marzotto M, Bonafini C, Olioso D, Baruzzi A, Bettinetti L, Di Leva F, Galbiati E, & Bellavite P (10 Nov 2016). Arnica montana Stimulates Extracellular Matrix Gene Expression in a Macrophage Cell Line Differentiated to Wound-Healing Phenotype. PLoS One, 11(11):e0166340. PMID: 27832158, PMCID: PMC5104438, DOI: 10.1371/journal.pone.0166340. ABSTRACT | FREE FULLTEXT PDF 

By Neuronicus, 10 June 2017