Durif 4.91 as approved grape varieties for American wines, but they are not listed as synonyms. This means that U.S. producers can produce Durif wine, but not label it as Petite Sirah, and vice versa. The ATF proposed that they be recognised as synonyms in "Notice of Proposed Rulemaking No. 941", published in the Federal Register on 10 April 2002, but a decision on RIN 1513–AA32 (formerly RIN 1512-AC65) appears to be postponed indefinitely, probably because the new regulation is tied up in the trade dispute that would see the TTB recognise Primitivo as a synonym for Zinfandel. While not one
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