Thursday, February 11, 2010

Personal Genomics and me

All the glossy magazines tell us that direct-to-consumer personal genomics is upon us and that our individual futures can now be predicted. Just because the science behind the predictions is (ahem) under-ripe does not mean that the whole venture is destined for extinction. Today’s undergraduates are highly likely to be consumers of information about their own genome and I hope they turn out to be informed ones. To this end, I’ll be integrating the topic of personal genomics into a two-class module on complex trait inheritance for a small introductory biology course. Next week.

So, yes, I’m feeling sleep deprived and jittery and I’m starting to dream about vanishing learning objectives, the way I used to dream about pushing electrons and sliding redox states as an undergrad. It’s only thanks to the mentoring of some helpful faculty members that I haven’t already burst into flames.

Assuming my lack of spontaneous combustion lasts until next Friday, this is what I’m thinking of trying:

Class I (2h minus break)
1) Social implications of disease testing – group disccusion of the reading
2) Huntington’s disease minilecture: Pedigrees, linkage and finding causative mutations by looking for markers physically linked to them
3) Activity drawing linked and unlinked alleles on chromosomes through the steps of meiosis and crossing over
4) Introduction to complex traits – examples of muliple genetic influences, environmental influences and gene x environment interactions
5) Brainstorm on ‘what is environment?’
6) Group activity on coming up with experimental designs to decide whether genetics or environment has more influence on a trait
7) Introduction to heritability
8) Think-pair-share on example of heritability misconception

Class II (2h minus break)

1) In-class quiz on homework problem set
2) Introduction to genome-wide association studies as a way to find linkage for complex traits and the current limitations on risks predicted from them.
3) In small groups, use the 23andMe demo genomes and answer guided questions to relate their existing knowledge of genes and alleles and loci and punnett squares and dominance relationships to the SNP genotypes on the screen. Group discussion of results.
4) Small groups each prepare a short genetic counselling session for either Lilly or Greg. Guided by fictional case notes for each that change the interpretation of the results.
5) Group synthesis of our interpretations of absolute vs. relative risk, genetic vs. environmental influences, actinable vs. non-actionable information.

Absurdly optimistic? Too dumbed down? I have no idea! Help!

You may notice that class II involves mostly footling around at the 23andMe website, looking at the demo genomes of ‘Lilly and Greg Mendel’ (not their real names). If you have never done this, I highly recommend it for late-night entertainment. The thing that bothered me at first was that my class could turn into a PR exercise, in which I tacitly endorse 23andMe by forcing my students to spend nearly 2 hours exposed to their advertising material. I’ve decided to go ahead with it anyway, because it's too nice an opportunity and I can at least summarise the uncertainties that hover around SNP risk estimates at the moment.

One last thing, I promise: I got a very interesting tip from the genetics lecturer in my department today. She said that she has struggled to get students to let go of the misconception that a complex trait is just a complicated one. The confusion is revealed when they always classify multi-allelic single gene traits as complex traits. It’s possible it would be easier for them if we jettisoned the term ‘complex’ and substituted ‘multifactorial’, but I still don’t know if there is some terminological difference between the definition of complex and multifactorial traits that I have missed.

4 comments:

Sandlin said...

Not that I have loads of experience in this, but if you have idea of how much time you want each of those activities to take, you can probably keep yourself on track schedule wise. But I find it hard to predict where students might completely miss the boat, so you have to stick on one subject for a longer time- this seems more likely to happen in the first day where the subjects build on each other- the students must understand environment before they can discuss it etc. Not sure how to deal with that, except to be flexible. And yet, I don't remember being profoundly confused by any of those particulars as an undergrad- I'm sure they'll lap it up like kitties. It seems like a good, engaging amount that should dispel confusion.

And about seeming like a poster for 23andme, it makes sense to stick with one website, but if it makes you feel better you could mention that similar resources exist for other companies with similar services. (IMHO 23andme does a better job at making that info interesting and accessible then the other sites I looked at.)

biology101 said...

Thanks Sandlin! I'm trying to scale back just a tiny bit. And not to freak out about the videotaping too much.

biology101 said...

Thinking more about the multi-allelic=complex misconception, I suspect it might actually be that they still don't have a clear understanding of the meaning of 'allele'. I definitely saw that problem in the genetics module I observed. In that case the confusion among the students was uncovered by the lecturer and was then the subject of class discussion, but I can imagine many students might otherwise leave introductory biology with only a hazy idea of what alleles are (beyond being upper-case and lower-case letters).

Sandlin said...

Yeah, I think you've hit the nail on the head- alleles are definitely a source of confusion. Almost understanding the term can lead to more confusion. Our HHMI discussion of personal genomics surely highlighted that (no, we can't get rid of the Huntington GENE, but we might screen for the Huntington disease ALLELE). All from kids who claimed to understand the concept.