A new preprint from the lab, with postdoc
@deboraycb.bsky.social and collaborators
@aidaandres.bsky.social and Tim Connallon:
“Characterising the detectable and invisible fractions of genomic loci under balancing selection”
www.biorxiv.org/content/10.6...https://www.biorxiv.org/content/10.64898/2026.01.13.698512v1
We combine theory and simulations to understand the propensity of mechanisms of selection (overdominance, antagonistic pleiotropy and sexual antagonism) to generate balancing selection that maintains stable polymorphisms, and to assess the power of current methods to detect them.
Jan 21, 2026 15:32Long-term polymorphism is more likely when Ne is large, balancing selection strong and frequency equilibria intermediate. This favours polymorphism under overdominance, which generates stronger selection and does so over a wider range of parameters than antagonistic pleiotropy or sexual antagonism.
The power of current inference methods to identify balanced loci is generally relatively low. However, it also varies substantially with allelic properties (selection strength , equilibrium freq., age), genomic context (recombination and mutation rates) and Ne and we quantify these effects.
A main conclusion from our work is that many balanced loci will remain undetected, and more or less so depending on the species. We're doing OK in humans (low Ne, r~mu), but Drosophila is much more challenging.
