Gamay Beaujolais was in fact the Napa Gamay. Moreover, Masson's Napa Gamay was found to not be a Gamay at all, but the Valdiguié grape from Languedoc-Roussillon. The US Alcohol and Tobacco Tax and Trade Bureau (TTB) subsequently discouraged the use of the term "Gamay Beaujolais" and ruled that, from 1997, it could only be used as a secondary designation on wines made from more than 75% Pinot noir or Valdiguié. Since April 2007, the term "Gamay Beaujolais" has been banned from labels in the United States. Gamay Beaujolais Gamay Beaujolais is a varietal designation for a Californian grape variety, an early
Petite mutation Petite mutation petite (ρ–) is a mutant first discovered in the yeast "Saccharomyces cerevisiae". Due to the defect in the respiratory chain, 'petite' yeast are unable to grow on media containing only non-fermentable carbon sources (such as glycerol or ethanol) and form small colonies when grown in the presence of fermentable carbon sources (such as glucose). The petite phenotype can be caused by the absence of, or mutations in, mitochondrial DNA (termed "cytoplasmic Petites"), or by mutations in nuclear-encoded genes involved in oxidative phosphorylation. A neutral petite produces all wild type progeny when crossed with wild type. petite mutations can