Friday, January 21, 2011
Do healthy marmots make better friends?
At the moment, this is what a typical day looks like for me. Here you see a collection of DNA samples, PCR tubes, pipettes, and a binder full of sequence data.
My research spans the disciplines of behavioral ecology and genetics in an attempt to link genetic differences among individuals with their behavioral consequences. I've spent a good deal of time in the field (see my other posts) observing and recording social interactions between individuals. In collaboration with my other marmot lab mates, I've also used quantitative genetic methods to estimate the relative importance of an individual's genetics vs. immediate environment in determining their actions in a social setting. Using this approach, we determined that an individual's genes do indeed influence it's social life and behavior...but which genes?
Quantitative genetics is a powerful tool for estimating heritability and identifying factors that explain variation in a trait, but to link a specific gene with individual differences we need to take another approach. Unfortunately, marmots are not a genetic model organism (like fruit flies, mice, or flatworms) and little is known about their genome. Therefore, I am targeting genes of demonstrated importance from closely related species and making an educated guess (a hypothesis!) about their function in marmots. I'm focusing on genes from the major histocompatibility complex (MHC), whose protein products play a crucial role in mammalian immune systems. Furthermore, we know that a marmot's body condition (a measure of overall health and vigor) influences it's social behavior, adding further support to my hypothesis that genetic differences at MHC loci influence social behavior. Theoretically, individuals with robust immune systems (coded for in their DNA) and superior body condition are preferable social partners; I know I would rather interact with a healthy friend that is less likely to get me sick!
So I am currently sequencing MHC genes of 48 marmots (some highly interactive, others quite antisocial) to get at this question. It requires lots of long days in the lab and lots of time in front of a computer screen...but I know the results will be worth it. Stay tuned for updates on how genes influence marmot social behavior!