Editing Ascomycota (section)

=== Heterokaryosis and parasexuality ===
Several Ascomycota species are not known to have a sexual cycle. Such asexual species may be able to undergo genetic recombination between individuals by processes involving ''heterokaryosis'' and ''parasexual'' events.

Parasexuality refers to the process of heterokaryosis,<ref>{{cite book |last1=Cole |first1=Garry T. |title=Medical Microbiology |date=1996 |publisher=University of Texas Medical Branch at Galveston |isbn=978-0-9631172-1-2 |edition=4th |chapter-url=https://www.ncbi.nlm.nih.gov/books/NBK8099/ |chapter=Basic Biology of Fungi }}</ref> caused by merging of two hyphae belonging to different individuals, by a process called ''[[anastomosis]]'', followed by a series of events resulting in genetically different [[Cell nucleus|cell nuclei]] in the [[mycelium]].<ref>{{harvnb|Deacon|2005|pp=164–6}}</ref>
The merging of nuclei is not followed by [[meiosis|meiotic events]], such as [[gamete]] formation and results in an increased number of [[chromosome]]s per nuclei. ''[[Mitotic crossover]]'' may enable [[genetic recombination|recombination]], i.e., an exchange of genetic material between [[homologous chromosome]]s. The chromosome number may then be restored to its [[ploidy#Haploid and monoploid|haploid]] state by [[Telophase|nuclear division]], with each daughter nuclei being genetically different from the original parent nuclei.<ref>{{harvnb|Deacon|2005|pp=167–8}}</ref> Alternatively, nuclei may lose some chromosomes, resulting in [[aneuploid]] cells.  ''Candida albicans'' (class Saccharomycetes) is an example of a fungus that has a parasexual cycle (see [[Candida albicans]] and [[Parasexual cycle]]).