grading continues

[sciatrix]

...but at least I'm just doing the extra choice question now, in which students propose a future lab experiment they'd like to do over the course of the (~twelve-week) lab. They're supposed to explain what model system they want to use, the learning objectives the lab would accomplish, and the experimental idea itself.

Here are some of the more entertaining suggestions, organized by category:

Wildly Ambitious And Totally Impractical:
-"we could do an addiction genetics experiment locating a gene implicated in alcohol addiction in mice, including exposing mice to steady alcohol and measuring withdrawal levels!"
-"we could look at epigenetics in fruit flies by exposing successive generations to limited nutrients and seeing how this changes methylomes!"
-"what if we [made up the concept of ChIP-SEQ] and did that on human DNA"
-let's look at gene by environment interactions in zebrafish embryos!
-let's make our own GMO crops in the lab!
-let's genetically modify a line of human T cells that will then express a specific antigen receptor, using viral vectors to modify the cells and then testing them on a cancer line! (bless this student, who ended their answer with "you would need loads of money to pull this off and probably the entire semester for students to make it work, and also waivers for working with viruses--but it would be so cool!!!")
-can we make a hybrid fruit like a tangelo and breed plants for desired traits?
-what if we MADE HUMAN CANCER by targeting p53 and transgenically destroying it in human cell tissue?

Could We Genotype Ourselves More?*
-what if we tested everyone in the lab for a locus controlling how cilantro tastes
-what if we did ancestry testing on ourselves like in 23 and Me
-what if we all checked to see if we were pre-disposed to a disease
-what if we did a forensic hair analysis and then extracted DNA and tested the genes from our hair?
-what if we sampled our skin's microbiome and sequenced it? or our mouths? or other parts of ourselves?
-what if we typed our own blood?
-what if we sequenced everyone and made a phylogenetic tree of the whole class?
-what if we did the same thing but we extracted proteins from our own blood instead?
-what if we tested the whole class for Huntington's?

Entertaining Suggestions
-"what if we repeated the fly lab to study Mendelian assortment but using guinea pigs or mice instead? Then we could pet them."
-"what if instead of using fly eye color we looked at mutations like EXTRA EYES OR MOUTHS"
-"what if we tested to see if vegan/vegetarian products are actually meatless?"
-"use a less-annoying novel organism for inheritance patterns"
-"what if we extracted DNA from all of our pets and did a cladogram of them"
-"could we create illustrations using streaking of bacterial with plasmids incorporating fluorescent proteins onto plates? we could use strains with different colors!"
-"what if we did a species ID lab with fruits so we didn't have to smell the fish smell?"
-"what if everyone genotyped their dogs and then brought in the dogs so we could pet them as we reviewed the results? I like petting dogs."

Actual Potentially Workable Ideas
-"Could we try using CRISPR/CAS in bacteria? It's an important technique, and I think that it would be good for us to understand how it works."
-"What if we cultured the bacteria living on our hands or our cell phones and then did a metabarcoding study on the colonies we isolated?" (probably a little too ambitious, but could be workable)
-"What if we did a mouse experiment where we collect the DNA from different tissues?" I'm going to guess that my students are not going to be proficient enough to play with RNA transcriptomics, but this would definitely be a fun project if I trusted them not to contaminate the RNA.
-"What if we did a study with C. elegans involving checking the motility of two different genotypic lines to show how behaviors can be underlaid by genetic variation?"
-"What if we tested the accuracy of various types of PCR on a human sample?"
-"Could we look at RNAi, maybe in C. elegans?"

_{*We already do two separate labs involving extracting and isolating students' own DNA, including a modified VNTR/DNA fingerprinting lab and a population genetics lab involving a neutral locus. These tend to be very popular with students when they work, although the fingerprinting lab, which requires students to estimate their allele frequencies in the context of ethnicity, can be a nightmare for us when students don't enter their own data (and we have to put something in on ethnicity) or when students are mixed-race and quite reasonably think that categorizing themselves is kind of dumb. I had one student a few years ago who pointed out that he could easily categorize himself as African, Asian, or European all at once, and what the hell should he put down?}

Comments

[hellofriendsiminthedark]

Testing the whole class for Huntington's feels unnervingly unethical to me, but then I read "what if we tested to see if vegan/vegetarian products are actually meatless?" and I was horrified and forgot all about it.

[sciatrix]

Oh, their suggestions are frequently unnervingly unethical. They've never thought through the implications of their suggestions, especially as applied to looking at humans and their own data. For one thing, they frequently suggest trying to test their own family members as well as themselves to look at patterns of inheritance, which tells me they've never considered the concept that maybe your dad isn't your biodad and that students for whom this is true may or may not know that ahead of time.

This is totally one of the reasons I write them down and share them in places my students will never see.

[conuly]

For one thing, they frequently suggest trying to test their own family members as well as themselves to look at patterns of inheritance, which tells me they've never considered the concept that maybe your dad isn't your biodad and that students for whom this is true may or may not know that ahead of time.

This specific issue seems to be a chronic problem in introductory bio teaching at all levels, from elementary school on up.

[sciatrix]

Fortunately most of the simple human Mendelian genetics examples aren't actually inherited in a simple, single-locus Mendelian manner, so it doesn't raise as many questions as you might think. (The only exception I know of is dry vs. wet earwax, and that's a) strongly racially distributed, such that you're likely to get all the kids of Asian descent with your dry samples and your European and African-descended kids with wet, and also b) gross to phenotype.)

The linked article suggests that people teaching genetics try using cats as an example, but I have also seen good results from using Burmese python colors.

[conuly]

And I was just about to link YOU to that article! (As they also point out, iirc, a lot of the examples they ask high schoolers to identify for themselves either aren't really heritable at all, or are super complicated and inappropriate as a teaching example anyway.)

Funny anecdote on that point, my mother bumped into this in high school biology. Her teacher had explained that blue eyes are an example of a recessive trait, and my mother, not thinking through the implications, asked "What about me? My father has green eyes and my mother has gray eyes, but mine are brown?" at which point her teacher quickly switched the topic. My mother swears she didn't know what the issue was until a few days later, when the teacher pulled her aside after class and said she'd done a lot of research and it turns out that green eyes and grey eyes can have hazel eyed children, and look, her eyes are hazel! And so they are. If that teacher had ever met my mother's parents she might not have bothered - Mommy looks very much like BonPapa and always has.

[sciatrix]

LOL oh man, that's.... so very awkward. I've never had that come up in class, but I can imagine dealing with it.

I link that article to people teaching genetics a lot! So far no one wants to take me up on the offer to compare earwaxes. I actually also often link students to this resource on dog genetics as a teaching aid too, come to think of it--lots of complex single-locus Mendelian traits with real-world dog pictures, too.