BACKGROUND: The adaptation of pathogenic fungi to the host environment via large-scale genomic changes is a poorly characterized phenomenon. @entity1327 is the leading cause of @entity364 in @entity645 / @entity791 @entity1 , and we recently discovered clinical strains of the fungus that are disomic for chromosome 13. Here, we examined the genome plasticity and phenotypes of monosomic and disomic strains, and compared their virulence in a @entity19 model of cryptococcosis RESULTS: In an initial set of strains, melanin production was correlated with monosomy at chromosome 13, and disomic variants were less melanized and attenuated for virulence in @entity19 . After growth in culture or passage through @entity19 , subsequent strains were identified that varied in melanin formation and exhibited copy number changes for other chromosomes. The correlation between melanin and disomy at chromosome 13 was observed for some but not all strains. A survey of environmental and clinical isolates maintained in culture revealed few occurrences of disomic chromosomes. However, an examination of isolates that were freshly collected from the cerebrospinal fluid of @entity791 @entity1 and minimally cultured provided evidence for infections with multiple strains and copy number variation. CONCLUSIONS: Overall, these results suggest that the genome of @entity1327 exhibits a greater degree of plasticity than previously appreciated. Furthermore, the expression of an essential virulence factor and the severity of disease are associated with genome variation. The occurrence of chromosomal variation in isolates from @entity791 @entity1 , combined with the observed influence of disomy on virulence, indicates that genome plasticity may have clinical relevance.

Variation in chromosome copy number influences the virulence of XXXX and occurs in isolates from @entity791 @entity1 .

@entity1 :: ('9606', 'Species') :: ['patients'] @entity19 :: ('10090', 'Species') :: ['mice', 'mouse'] @entity1327 :: ('5207', 'Species') :: ['Cryptococcus neoformans', 'C. neoformans'] @entity645 :: ('57667', 'Species') :: ['HIV'] @entity364 :: ('MESH:D009181', 'Disease') :: ['fungal meningoencephalitis'] @entity791 :: ('MESH:D000163', 'Disease') :: ['AIDS']
@entity1327 :: (5207,Species) :: ['Cryptococcus neoformans']
