Genome analysis shows yeasts evolving by subtraction


In Wisconsin, a team of researchers led by labs at the University of Wisconsin–Madison and Vanderbilt University sequenced and compared the genomes of 332 species of budding yeasts, all members of a subphylum of yeasts that multiply by producing daughter cells from buds on their surface. More than 200 of the yeast types had their genomes catalogued for the first time for the study.

“This is the first large genome project like this that actually looks at hundreds of different eukaryotic species, not different individuals or isolates of the same species,” says Chris Todd Hittinger, a UW–Madison genetics professor and one of the senior authors of the study. “Budding yeasts, despite their phenotypic similarity, are very different from one another genetically. They’re as different from one another as all animals or all plants are from one another.”

Collecting such a deep pool of yeast types gave researchers enough information to use comparisons of the shifting genetics to redraw the budding yeast family tree into a dozen major branches and paint a detailed picture of their past.