[ed: it's been a while since I've posted, mostly because not much happened.]
While it's officially Week 5 in a 7-week course, I'm actually well into Week 6 (weekly content is released a week in advance), with only one quiz to take − I expect to do it later today − then it's down to the dreaded peer-reviewed essay.
All this to say that I feel capable of discussing the course.
(to digress, there's something I thought about yesterday: MOOCs are supposed to be “communities” for students, but they are transient − lasting only a handful of weeks. For the same reason it's hard to be able to discuss a course in general terms based on only a couple of weeks' content, it's difficult to get to know people − fellow students − in such a short time. I wonder if multiple-course sequences, like the ASTROx year-long series at ANU, will actually foster such a “community”.)
Anyway − epigenetics is the study of the process through which genes are stably turned on or off. The keyword here is “stably” − while a given cell will express genes differently at various times (for instance insulin secretion is turned up when glucose enters the pancreatic beta-cells), this is not an epigenetic change; rather, some genes are permanently turned off (or on) for the whole life of the cell, barring exceptional circumstances, and this state is preserved when the cell multiplies.
Something which the course makes very clear is that this is a field under active research. In other words, there is very little that we know for certain − some processes are well-understood, but most are not, and a large part of what is thought is “very controversial”, that is to say, researchers disagree strongly on how the mechanisms work, and even on whether they actually exist in the first place. So that's pretty exciting, if somewhat confusing: one doesn't quite expect to walk into a classroom and be told “okay, so we think there is some epigenetics here, but we're not sure, and we don't really know how it works anyway, so if you're thinking of doing some research of your own in the future, that's not a bad place to start.”
In keeping with this bleeding-edge focus, the course places a strong emphasis on reading scientific papers, over at PMC or PLOS − we're actually quizzed on the papers. In a way, the video lectures are only an introduction, the real meat of the course being the papers. That's the hardest part for me: reading and understanding jargon-laden, dry papers is a specific skill that I, erm, need to work on (I find my eyes glaze over pretty quickly). It's also not an activity that can easily fit into my normal MOOCing times (on the bus/train? No way, requires much more concentration − in the evenings? Nope, requires a freshness of mind that I just don't have after a full day's work − ideally I'd get up an hour earlier and read during breakfast, but er… I value sleep, too).
In terms of content: the first few weeks are about the well-understood mechanisms (DNA methylation, chromatin structure and histone modifications, X chromosome inactivation, epigenetic reprogramming), then we get on to more controversial topics (environmental disruption of epigenetic state, for instance the effects of tobacco smoke, or diet, at crucial periods of time). The last week of the course is about cancer, which is pretty interesting (epigenetic modifications are one of the hallmarks of cancer − it's actually one of the very few common points of all cancer types: not knowing anything about the subject, I'll refrain from qualifying cancer as an “epigenetic disease”, but it's certainly tempting.)
The lectures are basically slides with an embedded shot of the lecturer (Marnie Blewitt from Melbourne University) in the corner. While I usually dislike this format, here it works well, partly because Dr Blewitt is a great speaker with a clear voice, but mostly because the slides are only outlines / supporting material for the course itself. In fact I find I hardly read the slides − I just skim them and concentrate instead on the audio.
Every week there's a quiz, which is fairly difficult − you have three tries, but the questions change between each try. As I said, the quizzes are often about specific points raised not in the lecture, but in the required readings, forcing us to read the papers, not a bad thing. At the end of the course, there is a peer-reviewed essay; I'm not certain how it will play out, it's been ages since I wrote essays (and then again, never in a scientific subject). I'll keep you posted about how it turns out.
So, in general, I like this course quite a lot, and it's certainly given me a lot of things to think about.
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