Education and Experience

Informatics Leader, Genomic Diversity Facility, Cornell University. July 2014-present.
Research Associate, Bioinformatics Facility, Cornell University. August 2012-present.
Postdoctoral Researcher, Cornell University. March 2012-August 2012.
Postdoctoral Researcher, UMass Amherst. 2011-2012.
PhD Evolution, Ecology and Population Biology, Washington University in St. Louis. 2010.
MS Microbiology and Molecular Genetics, Michigan State University. 2004.
BS Microbiology and Molecular Genetics, Michigan State University. 2004.

Current Research

VitisGen: Accelerating Grape Variety Development via Next Generation DNA Sequencing

Past Research

Genetic evidence suggests that strains of Saccharomyces cerevisiae used to make wine may be domesticated. Although S. cerevisiae has been isolated from trees, soil, indigenous fermentations and clinical sources as well as vineyards and wine fermentations, the genetic variation that exists within the vineyard and grape must strains is a subset of the genetic variation that exists within the species as a whole. While a bottleneck pattern is consistent with domestication, it could also be the consequence of a complex population history rather than adaptation to wine making. To distinguish between these hypothesis I investigated genetic and phenotypic variation between vineyard and non-vineyard strains of S. cerevisiae.
If vineyard strains are locally adapted we expect selection to limit gene flow between sympatric vineyard and arboreal isolates. To address this question, I collected and characterized yeast from grapes, trees and soil at vineyard and non-vineyard locations during the grape harvest season.
Domestication is typically characterized by a suite of adaptive traits referred to as the 'domestication syndrome.' Potential domestication traits in S. cerevisiae could include growth and fermentation phenotypes that lead to fitness differences, as well as differential production of metabolic products that affect wine aroma and flavor. I measured growth rate as a proxy for fitness over varying environments, and also completed sensory analyses using wines fermented from vineyard strains, oak tree strains, and other Saccharomyces species.

Mixing of vineyard and oak-tree ecotypes of Saccharomyces cerevisiae in North American Vineyards

Divergence in wine characteristics produced by wild and domesticated strains of Saccharomyces cerevisiae

Genetic and Phenotypic Differentiation between Winemaking and Wild Strains of Saccharomyces cerevisiae