Tag Archives: control group

Tackling GMO’s Part 4. G.E. Séralini case. Why it is both pivotal and pointless.


It’s about time I got back into this, here we go!

If you’re digging through the facts about GMO food, especially if you’re going from the popular media, eventually you’ll be brought back to one report. This report, headed by one Gilles-Eric Séralini, can be found here. Now, this report has since be redacted, and, if you look below the main article, you will see that the article itself has been heavily criticized within the journal itself.

I’ve already stated before that I am pro GMO (over all, it isn’t perfect, but those problems almost exclusively fall into farming practices, not the GMO’s themselves). The data that exists overwhelmingly shows that as far as food crops go there is no significant harm to humans or even the environment in making or using GMO’s. However, the above paper, redacted or not, is still being used as a source to “prove” that GMO’s are toxic. There is numerous reasons why that is not the case and I’ll be going through some of those reasons.

I’d like to redirect to my previous post about statistical significance here before we go further for a refresher on what that means for those readers unfamiliar with the concept.

The first thing I will point out is the redaction of the paper. Redactions are rare in science. Generally they only occur when there is some form of scientific misconduct. From what I’ve gathered from the back and forth posts, Séralini has not been accused of any misconduct, however, the Journal’s representative indicated that the redaction is due to pushing from the scientific community, and because the article itself was inconclusive and couldn’t accurately draw the conclusions made by the research team.

This is my major complaint with the paper, and the most telling, although it isn’t the sort of stratifying headline that gets people’s attention. “Anti-GMO paper found statistically irrelevant, says Journal representative.” Just doesn’t have a nice ring to it. This lack of statistical significance is why I call it a pointless paper because it really doesn’t say anything, but allow me explain why.

Generally the upper cut off in the biological sciences for a result to be statistically significance is 5% (though it is often only consider accurate when that percentage is much lower). What that means is that there is only a 5% chance that the results are just a fluke that can be explained by random chance. The primary ways of lowering the risk of statistical insignificance are to increase the population or sample size you’re researching and reduce the number of thing you’re studying and testing for (to better make use of your limited sampling population).

So this bring us to back to the Séralini paper. In the post analyst of the paper by researchers who also use rats for toxicity testing (a very routine bit of science) that suggested that the paper would have done much better to have at least over 200 rats, and Séralini and his team only used 100 each of males and females. Why so many rats? Well Séralini wasn’t just testing one factor he was testing the effects of Roundup and a Monsanto corn feed, splitting up by sex. So You have the rats split into 10 equivalent groups a control group and 9 treatment groups for both male rats and female rats. 6 of the control groups contained GM corn feed and the feed was either treated with roundup or not with each group given different level of roundup in their corn feed. the final three treatment groups were fed control (a similar non-gm corn) feed and tap water contaminated with some level of round up. Again all the group had different levels of round-up treatment.

If you’ve done the math that means each group only has 10 individuals in it. That’s a tiny sample size, and while there is some overlap, it’s like the team was trying to do three or four experiment in one, and they definitely did not use the resources they need to pull that off.

Why? Because 10 individual is almost never enough to draw any sort of accurate conclusions. There is simply to much room for mistakes or randomness to dictate the results. And even though there is some overlap in the treatment groups, this can’t help since the control group, which forms the basis of comparison of every other group, still only contains 10 individuals, so any of the inconstancies could easy wind up there. Regardless, you can’t pull off accuracy with such small sample sizes and without a group (the control group) to compare to you can’t actually say anything about it one way or another, since the statistics could be normal, but you can’t be sure since you lack a population to compare too.

Though this isn’t the only issue I have with the paper, besides being a pointless and useless waste of time and resources, because it could never be statistically significant, the treatment of the animals was unethical. If you look at the paper (I won’t share them here as they are pretty gruesome) you’ll see some pictures of 3 rats with massive tumors, though problematically only three of the rats. If you where being unbiased, you’d include the pictures of all rats, though, since the pictures had nothing to do with the results, I suspect they where added only for shock value. And they are shocking. You have three rats who by mass are over 25% tumor. Swollen to the point they problem would have great difficulty moving and be in great pain.

Before you panic, cancer in rats is abnormally common compared to other mammals, and the line of rat used in the paper have the terrible tendency to form these sorts of tumors spontaneously 30-50% of the time no matter what else you might do to them. So it might be the case that the research team picked this group of rats specially because they would form these “showy” tumors spontaneously.  But, more over, they allowed some of the rats to live longer than the average life span of these sort of rats, and probably simply to take those shocking pictures. Though we won’t actually know that for sure as the original data from the experiment was never released, so we don’t know which rats were which or what the original data collected was. This little fact is also damning since it make replication and comparison much more difficult, since you don’t know what all the outcomes actually are.

There is plenty else wrong with the paper: it’s hard to read for a scientific paper, the figures are unclear and overcrowded, and certain other results where ignored in the conclusion (like that one group of male rats which drank round up contaminated water actually had a longer life span then the control group). Though, again, all of these data points are statically irrelevant, so ultimately all of the result are meaningless.

Another damning fact surrounding the paper is that Séralini, while creating a lot of hype before the paper was published (which itself was odd given how poor it is overall), would not allow reporters to read the paper until they sign a legal document to promise that they would not share the document with other people (including trained scientists in the field) until after the paper was finished, so reporters had no means of fact-checking the legitimacy of the paper. And no other scientists were allowed to read the paper prior to publishing. A very odd thing to do unless you know your result are suspect.

So this paper, pivotal to so many anti-GMO arguments, is in fact a pointless bit of research that says nothing about the Monsanto products it was studying, but does speak poorly of those researcher who worked on it. I suggest if you see the name Gilles-Eric Séralini you’d be best to proceed with a healthy dose of skepticism.

There has been no shortage of criticism of this paper, and here is a very thorough tear-down of the paper. It does a better job than I do. Though, after searching through Youtube, this is the only video that accurately address the paper. That is, actually talks about the paper itself rather than working around it or just addressing the criticism. However, after carefully looking around, this is the most thoughtful and, most importantly, thorough I could find. So thanks to Myles Power for being awesome and stuff. I’ll definitely be linking to him more in the future:

https://www.youtube.com/watch?v=OWQON4FzQo4

Oh and why it the study pivotal? That because it’s the crux of some many GMO arguments, understanding that the science doesn’t support the vast majority of anti-gmo claims particularly this “paper” it key to getting a problem understanding of the issue and tackling this problem people have with GMO’s