A New Lineage of Cryptococcus gattii (VGV) Discovered in the Central Zambezian Miombo Woodlands.
We discovered a new lineage of the globally important fungal pathogen on the basis of analysis of six isolates collected from three locations spanning the Central Miombo Woodlands of Zambia, Africa. All isolates were from environments (middens and tree holes) that are associated with a small mammal, the African hyrax. Phylogenetic and population genetic analyses confirmed that these isolates form a distinct, deeply divergent lineage, which we name VGV. VGV comprises two subclades (A and B) that are capable of causing mild lung infection with negligible neurotropism in mice. Comparing the VGV genome to previously identified lineages of revealed a unique suite of genes together with gene loss and inversion events. However, standard restriction fragment length polymorphism (RFLP) analysis could not distinguish between VGV and VGIV isolates. We therefore developed a new RFLP method that can reliably identify the newly described lineage. Our work highlights how sampling understudied ecological regions alongside genomic and functional characterization can broaden our understanding of the evolution and ecology of major global pathogens. is an environmental pathogen that causes severe systemic infection in immunocompetent individuals more often than in immunocompromised humans. Over the past 2 decades, researchers have shown that falls within four genetically distinct major lineages. By combining field work from an understudied ecological region (the Central Miombo Woodlands of Zambia, Africa), genome sequencing and assemblies, phylogenetic and population genetic analyses, and phenotypic characterization (morphology, histopathological, drug-sensitivity, survival experiments), we discovered a hitherto unknown lineage, which we name VGV (variety five). The discovery of a new lineage from an understudied ecological region has far-reaching implications for the study and understanding of fungal pathogens and diseases they cause.
|Year of Publication||
2019 11 12
|PubMed Central ID||
MR/N006364/1 / MRC_ / Medical Research Council / United Kingdom
U19 AI110818 / AI / NIAID NIH HHS / United States
MR/R015600/1 / MRC_ / Medical Research Council / United Kingdom