Balancing Selection: methods, signatures, mechanisms

Balancing selection is an umbrella turn for several evolutionary mechanisms through which adaptive variation is maintained in populations. While it is often understood as simply overdominance or heterozygote advantage, it encompasses not only that mechanism, but also antagonistic selection, fluctuating selection in time/space, negative frequency dependent selection, to name a few.

I first started working with balancing selection in my Masters, where I focused on HLA (human MHC) genes and their evolution. I showed that those genes in humans harbour signtures os divergent allele advantage (a particular form of overdominance). I then became more interested in balancing selection at large, and focused on understanding its impact in human evolutionary history in my PhD. Co-supervised by Aida Andrés and Diogo Meyer, and with several collaborators, we created a new method tailored to detect signatures of long-term balancing selection, which has since been implemented by researchers studying humans (e.g., here, and here) and non-human organisms (e.g., a copepod), and at least one modification of our original method has been developed.

In collaboration with the Meyer Lab, I’ve written a review on the genomics of HLA evolution, where balancing selection is a key factor.

You can find the GitHub repo with the code for the NCD-statistics here.

This is an ongoing topic of interest for me, and I am activley looking for guest lecturer teaching opportunities and collaboration opportunities, so do reach out if you’re interested in either of these.