Genetic differentiation of the sherry yeasts Saccharomyces cerevisiae

Molecular and genetic studies of the yeast Saccharomyces cerevisiae isolated at distinct stages of sherry making (young wine, solera, and criadera) in various winemaking regions of Spain demonstrated that sherry yeasts diverged from primary winemaking yeasts according to several physiological and molecular markers. All sherry strains, regardless of the place and time of their isolation, carry a 24-bp deletion in the ITS1 region of ribosomal DNA, whereas the yeasts of primary winemaking lack this deletion. Molecular karyotypes of sherry yeasts from different populations were found to be very similar.