Recovering genomes from uncultured fungi with single-cell genomics

Single-cell genomics (SCG) complements culture-independent metagenomics for accessing fungal genomes, particularly from lineages that remain uncultured. We contrast metagenomics, which excels when profiling community composition and metabolic potential but often underrepresents low-abundance fungi, with SCG, which first isolates individual cells or nuclei to generate single-amplified genomes (SAGs) and can recover rare or microdiverse taxa. We then organize existing fungal SCG applications into three subgroups: spore-level sequencing from host-enriched or environmental material; single-nucleus genomics for multinucleate fungi; and single-spore sequencing of haploid progeny for diploid linkage and chromosome phasing. Across studies, pooling and co-assembly of cognate cells improves completeness; key hurdles persist in wall lysis, whole-genome amplification bias, and contamination control. Practical advances include shallow sequencing for QC triage, nuclei pooling with normalized co-assembly, and hybrid long- and short-read assembly. SCG adds unique value where strain resolution and genotypic context matter, including host-to-mobile-element linkage, recovery of large biosynthetic gene clusters, and karyotype validation against telomere-to-telomere references. Used alongside metagenomics, SCG enables a strain-resolved view of fungal biodiversity and function, with incremental improvements across the SCG pipeline promising routine access to genomes from early-diverging and other environmentally embedded fungi.