The complete genome of a songbird

Bird genomes are the smallest among amniotes; however, they remain challenging to assemble due to their structural complexity. This study presents a fully phased diploid telomere-to-telomere reference genome for the zebra finch (Taeniopygia guttata), a model organism for neuroscience and evolutionary genomics. Combining sequencing strategies allowed the closing of nearly all gaps, adding ∼90 Mbp of sequence (7.8%). The assembly contains gapless sequences for all microchromosomes, including the elusive dot chromosomes with their distinctive architecture. The genome was comprehensively annotated for genes, repeats, and structural variants. Complete centromeres were identified, along with candidate DNA-binding centromere protein B (CENP-B) homologs, suggesting that birds possess a kinetochore-associated CENP system similar to that of mammals. Relative to the previous reference generated by the Vertebrate Genomes Project, 2,710 (8.13%) previously unassembled or unannotated genes were identified. This complete genome of a songbird serves as a public reference and illuminates avian genome architecture and function.