The dynamics of transposable element content in the genome of the human pathogen Histoplasma.

Histoplasma is a genus of human fungal pathogens that frequently affects immunosuppressed patients. Previous genetic surveys have largely focused on nucleotide-level variation, but much less attention has been given to more complex forms of mutation. Among these, transposable elements (TEs) represent an important class of mobile genetic elements that can alter genome size and play key roles in adaptation and speciation. In this study, we address this gap by examining the content and evolutionary dynamics of TEs in the human pathogen Histoplasma. Using previously published Histoplasma genome assemblies, we quantified TE content across eight phylogenetic species within the genus. Our analyses reveal heterogeneity in the evolutionary patterns of different TE families. The majority of TE orders and superfamilies show strong phylogenetic signal suggesting that phylogenetic relatedness significantly constrains the content of mobile genetic elements. We find no correlation between RNA or DNA TEs and genome size. Together, our results highlight the diverse landscape of TEs in Histoplasma and suggest that future studies should investigate their impact on genome evolution, fitness, and virulence.