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The genetic diversity of ''Brettanomyces'' is particularly wide. Some studies have indicated that strains of ''B. bruxellensis'' have adapted to specific environments. For example, one study found that strains of ''B. bruxellensis'' isolated from wine had 20 genes involved in the metabolism of carbon and nitrogen, whereas strains isolated from beer did not. This indicated that ''B. bruxellensis'' strains living in wine have adapted to the harsher environment of wine <ref name="smith_divol_2016"></ref>. Another study found that one out of the two strains tested that were isolated from soda could not ferment maltose, and only strains isolated from wine were able to grow in wine and the beer/soda strains did not. The wine strains were also more resistant to sulfites, which are commonly used in the wine industry to prevent microbial contamination <ref name="Crauwels_2016" />.
A genetic survey of 1488 different strains of ''B. bruxellensis'' from 29 countries, 5 continents, and 9 different fermentation niches was conducted in 2018 by Avramova et al. They found that these strains formed roughly 5 genetic groups with mostly separate ancestral lineages, and 1 group with a mixed ancestral lineage: 3 wine groups, 1 beer group, 1 kombucha group (most distantly related to the beer group), as well as 1 tequila/ethanol group that has multiple ancestral lineages. Additionally, This was expressed mostly in the ploidy level of each group (the number of sets of chromosomes) were different for each group, with 2 of the wine groups, the tequila group, and the beer group containing more sets of chromosome pairs than the other groups (diploid vs triploid; this is thought to encourage adaption and hybridization). Additionally, the triploid groups were wine group was generally more tolerant of SO<sup>2</sup> than the diploid wine groups. The genetic differences of genetics between the fermentation substrate substrates (beer, wine, etc.) were lower but still significant, and this was explained by the frequent cross-over of equipment such as wine barrels being used for beer fermentation. When comparing the geographic differences, they found that the strains were loosely related based on their locale, but there was a larger dissemination of the wine strains across the world, suggesting that beer, kombucha, and tequila strains are more localized geneticallythan wine strains. They also found that although one study reported spore-forming versions of ''B. bruxellensis'' (referred to as ''Dekkera bruxellensis''), the genetic makeup of the analyzed strains determined their ability to sporulate to be non-existent or rare <ref>[https://www.nature.com/articles/s41598-018-22580-7 Brettanomyces bruxellensis population survey reveals a diploid-triploid complex structured according to substrate of isolation and geographical distribution. Marta Avramova, Alice Cibrario, Emilien Peltier, Monika Coton, Emmanuel Coton, Joseph Schacherer, Giuseppe Spano, Vittorio Capozzi, Giuseppe Blaiotta, Franck Salin, Marguerite Dols-Lafargue, Paul Grbin, Chris Curtin, Warren Albertin & Isabelle Masneuf-Pomarede. 2018. doi:10.1038/s41598-018-22580-7.]</ref>.
Sulfite and SO<sub>2</sub> inhibits the growth of ''Brettanomyces'', and is often used in the wine industry to prevent the growth of ''Brettanomyces'' (some wineries have identified small amounts of flavors from ''Brettanomyces'' as being beneficial to certain wine styles, and is said to increase the complexity and impart an aged character in young wines <ref name="smith_divol_2016"></ref>) <ref>[http://onlinelibrary.wiley.com/doi/10.1111/j.1745-4549.2012.00702.x/abstract Removal of Brettanomyces Bruxellensis from Red Wine Using Membrane Filtration. Umiker, Descenzo, Lee, and Edwards. 04/24/2012.]</ref>. However, it has been shown that wine strains of ''B. bruxellensis'' could survive dosages of up to 1 mg/L of SO<sub>2</sub>, and the very high dosage of 2.1 mg/L was needed to kill ''Brettanomyces'' in wine <ref name="Agnolucci_2017" />. This dosage of SO<sub>2</sub> is beyond legal limits and has negative effects on wine. The tolerance of SO<sub>2</sub> of strains of ''Brettanomyces'' found in beer is lower than those found in wine strains. Some strains of ''Candida pyralidae'', ''Wickerhamomyces anomalus'', ''Kluyveromyces wickeramii'', ''Torulaspora delbrueckii'' and ''Pichia membranifaciens'' have been found to produce toxin that inhibits ''Brettanomyces'', and these toxins have been proposed as an alternative to SO<sub>2</sub> as a way to kill ''Brettanomyces'' (killer wine strains of ''Saccharomyces cerevisiae'' do not kill ''Brettanomyces''; see [[Saccharomyces#Killer_Wine_Yeast|Killer Wine Yeast]] for more information).