Bia blanc blanche, Peloursin, Servanin and Verdesse. Over the years, Bia blanc has been known under a variety of synonyms including: Bear, Beard and Biard. Bia blanc Bia blanc is a white French wine grape variety that is no longer commercially cultivated for wine production with only a few plantings existing worldwide in viticultural archives and experimental vineyards. The exact origins of Bia blanc are not yet known though ampelographers have noted that the grapevine shares some morphological similarities to the red Isère grape Peloursin, one of the parent varieties to Petite Sirah (Durif). In the 20th century, ampelographers Louis Levadoux and
Petite mutation petite negative mutants. Potentially, these yeasts have a different inheritance system in place for their mitchondrial genome than "S. cerevisiae" does. The frequency at which "S. castellii" spontaneously produces petites is similar to that of "S. cerevisiae", with the mitochondrial DNA of those petites being highly altered via deletion and rearrangement. Suppressive petites of "S. cerevisiae" are the most commonly observed spontaneously created mutants, whereas in "S. castellii," the most commonly observed spontaneous mutant is the neutral petite, further leading to speculation that the transference of this mutation differs between species. Petite mutation petite (ρ–) is a mutant first discovered