Population genomics: Gene expression in a vineyard yeast from Tuscany.

We have shown the existence of manifest differences in gene expression in a vineyard isolate of *Saccharomyces cerevisiae*. The differences range across nearly all major categories of the MIPS database (Munich Information Center for Protein Sequences), but the most dramatic differences affect genes involved in central metabolism, particularly amino acid synthesis. The extent of variation in expression of such genes, the demonstrated heritability of the expression levels, and the possible relationship with the filigreed colony phenotype provide a novel opportunity to study the extent to which regulatory variation and its pleiotropic effects may be the raw material for evolutionary change.