The evolutionary benefits of aneuploidy

Duncan Greig (primary)
Genetics, Evolution, and Environment
Wenying Shou (secondary)
Genetics, Evolution and Environment


Changing the copy number of individual chromosomes allows yeast to gain or lose important phenotypes, including antibiotic resistance. Changes in copy number occur when chromosomes mis-segregate during cell division, and researchers believe that the probability of mis-segregation is optimised by natural selection as a form of bet-hedging. Yeast could hedge their bets by producing some otherwise-diploid offspring with extra copies of chromosome VIII, which are resistant to fluconazole, and others with decreased copy number, which can grow faster in the drug’s absence. We will develop theory, quantitative models, and wet lab evolution experiments to demonstrate the evolution of bet hedging.


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[2] Gilchrist, C., & Stelkens, R. (2019). Aneuploidy in yeast: Segregation error or adaptation mechanism? Yeast, 198, 715.

[3] McGrew, J., Diehl, B., & Fitzgerald-Hayes, M. (1986). Single base-pair mutations in centromere element III cause aberrant chromosome segregation in Saccharomyces cerevisiae. Molecular and Cellular Biology, 6(2), 530–538.

[4] Kumaran, R., Yang, S.-Y., & Leu, J.-Y. (2013). Characterization of Chromosome Stability in Diploid, Polyploid and Hybrid Yeast Cells. PLoS ONE, 8(7), e68094.

[5] Rogers, D. W., McConnell, E., Ono, J., & Greig, D. (2018). Spore-autonomous fluorescent protein expression identifies meiotic chromosome mis-segregation as the principal cause of hybrid sterility in yeast. PLoS Biology, 16(11), e2005066.

Plants, microbes, food and sustainability
Area of Biology
Techniques & Approaches
BioinformaticsGeneticsImage ProcessingMathematics / StatisticsMolecular BiologySimulation / Modelling