I'm teaching an undergraduate genetics class this term, as I often do. Last week, when I was at the grocery store waiting to check out, I saw a National Geographic publication called, "Your Genes: A User's Guide. 100 things you never knew." For $14.99 (plus tax), I took home a copy. After all, I figured, I should probably learn the 100 things before going back to class the following day.
I looked through the 100 facts, and made a not entirely surprising discovery: I was familiar with many, but there were some I didn't know. Most surprisingly to me, none of the facts were presented with citations to the original research. At the back of the issue, a page is devoted to all of the photo credits throughout the magazine, but there were no references to the facts! So, we have an issue (pun intended): a newsstand piece is offering facts about genetics, but it doesn't support information literacy because the reader has no easy way to independently verify the veracity of the claims!My mind was immediately made up: I'd ask my genetics students to participate in an assignment to create a bibliography of credible scientific literature to support or refute each of the facts. I usually have students practice using mobile devices in the same way that scientists do (e.g. looking up genetic information online - using trusted sources, of course!), so this assignment supports one of my student learning outcomes, "Efficiently find and use quality information relevant to genetics." I should also mention that this project is feasible because I teach a class in which all of my students are supported by my university in having a mobile device for in-class use if they do not already own one: the DISCOVERe Mobile Technology Program. One goal of this program is for students to master digital literacy skills.
Before starting, I wanted to know if some facts would be really difficult for my students to fact-check. So, I did what I'm good at: I made another spreadsheet. I typed out the 100 facts, and then I categorized them:
- 81 of the facts relate to topics I teach about in my genetics course
- 42 of those 81 immediately fail fact-checking for a number of reasons. Here are an example or two from several categories:
Semantics
#33. "The bacterium E. coli can replicate 1,000 nucleotides per second." The the real problem is the word "can." To the critical thinker, this could imply that in some trivial, artificial scenario, a bacterium is technically capable of such an act. If so, then would this be a fact? I suppose it would adhere to the technical definition of "fact," but would it be relevant to genetics in the sense of a valuable fact to know about biology and how cells work?
#5. "All of us get three feet (1 m) of DNA from our father and three feet from our mother" At the outset, there are two potential problems with fact-checking this. First, one of the key warning flags for spotting untruths is the absolute, like "all of us." In biology, there is almost always an exception to every rule, so in this situation, it is almost certain that an exception to this purported fact could be found. Also, a finer point: DNA is a molecule, and its length, like a rope, depends in part on how much it is stretched. This number, as presented, probably assumes some common knowledge of the chemical structure of DNA, but without that assumption explicitly accompanying this fact, there is no clear way forward for fact-checking it.
Ambiguity: vague or imprecise wording
#8. "More than 800 genes are involved in cell division." This fact seems likely true, but "more than 800" is vague. Additionally, "involved in cell division" is also imprecise. One could argue that DNA polymerase, the enzyme that replicates DNA, is involved in cell division because without it, cells wouldn't contain the 799 other genes otherwise involved in cell division. It is a slippery slope, and so the way this fact is worded makes it unable to fact-check, depending on who is defining what "involved in cell division" means.
#85. "Although James Watson and Francis Crick used x-ray data to visualize DNA, the real proof came in 1982 when the B-form of the molecule – the right-handed side of the helix – was crystallized." The real proof of what? We can't fact-check what we don't know what we're trying to find evidence for
Opinion
#76. "Rosalind Franklin’s x-ray photographs of crystallized DNA fibers are hailed as the 'most beautiful x-ray photographs of any substance every taken.'" We could probably find a source for who said this, and maybe it is a fact that this opinion was made, but that's irrelevant to genetics
#62. "The most useful stem cells come from human embryos." Most useful to who and for what?
#31. "Many scientists believe antisocial behavior is a function of genetics, as multiple genes work together." What "many scientists" (how many? a tiny minority?) have concluded is relatively difficult to fact-check, but more critically, a factual statement cannot contain the word "believe." What scientists believe (think) is not relevant to fact (what we know).
Definition (no real need to fact-check)
#53. "The entire genome of an organism is found in a donor, or somatic, cell." This isn't quite true, but (almost) every somatic cell does have a nucleus and so does contain the entire genome of the organism.
#39. "Each of us has 22 nonsex chromosomes." This is true, by definition: humans have 22 nonsex chromosomes and then the 23rd (the X and Y, or sex, chromosomes). Whether a definition comprises a fact is debatable, I suppose?
Predictive or otherwise not-fact-checkable
#79. "In less than 10 years, scientists will be able to sequence an entire genome in just a few hours." I guess we'll know in, at most, ten years! This also, as many of the facts, falls into multiple categories, like "Ambiguous." We can already sequence the entire genome of many species in just a few hours; presumably this fact is meant to be about sequencing a human-sized genome…
#13. "About 1 percent of the total DNA carries instructions to make proteins; the rest is so-called junk DNA." The first clause might be true (but, like #79, "the total DNA" of what organism? Also the second clause is arguable. Some used to call the non-protein-coding part of our genome "junk DNA," but that term has fallen out of fashion. We now better appreciate that sections of our DNA that don't contain genes still can have important functions. So, on one hand, many scientists would disagree that this is a fact, but the existence of the few who might still refer to it as "junk DNA" means that, technically (the way it is written), this is an indisputable fact.
Unimportant facts or definitions to be aware of (granted, "unimportant" is my opinion)
#98. "Aboard the International Space Station is a digitized copy of Stephen Hawking’s genome, along with that of Stephen Colbert and others." It is called the Immortality Drive - look it up on Wikipedia
#45. "'Quaternary marriages' are when identical twins marry identical twins."The remaining 39 of the 81 facts that are relevant to my genetics class are definitely in need of fact-checking, and my students and I will meet that challenge! Our findings will be shared here.
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