Abstract

Saccharomyces cerevisiae is extensively utilised for commercial fermentation, and is also an important biological model; however, its ecology has only recently begun to be understood. Through the use of whole genome sequencing, the species has been characterised into a number of distinct subpopulations, defined by geographical ranges and industrial uses. Here the whole genome sequences of 104 New Zealand S. cerevisiae strains, including 52 novel genomes, are analysed alongside 450 published sequences derived from various global locations. The impact of S. cerevisiae novel range expansion into New Zealand was investigated and these analyses reveal the positioning of New Zealand strains as a sub-group to the predominantly European/wine clade. A number of genomic differences with the European group correlate with range expansion into New Zealand, including 18 highly enriched SNPs and novel Ty1/2 insertions. While it is not possible to categorically determine if any genetic differences are due to stochastic process or the operations of natural selection, we suggest that the observation of New Zealand specific copy number increases of four sugar transporter genes in the HXT family may reasonably represent an adaptation in the New Zealand S. cerevisiae subpopulation, and this correlates with observations of copy number changes during adaptation in small scale experimental evolution studies.