Cracking the oat code: A comprehensive pangenome and pantranscriptome resource

Oat (Avena sativa) is a globally cultivated cereal for its rich dietary fiber and health-promoting benefits. Yet, despite its nutritional importance, oat genomics has long lagged behind other cereals due to its large, repeat-rich, and allohexaploid genome which does not generally recombine. In a recent landmark study, Avni and colleagues tackled this complexity by assembling 33 oat lines, including both wild and domesticated varieties, and profiling gene expression across six tissues and multiple developmental stages in 23 of them. The result is a comprehensive pangenome and pantranscriptome of hexaploid oat, predicting between 107,847 and 136,836 genes, with 60.5% showing expression. The team further characterized gene presence–absence variation and copy number variation, revealing a structured genomic landscape: a core genome (present in all lines) enriched in essential functions such as flowering, nutrient uptake, and cell wall organization; a shell genome (present in many lines) associated with defense, seed storage, and transcriptional regulation; and a cloud genome (present in single lines) containing genes for signaling and stress responses. Importantly, they linked structural variations to agronomic traits, including an inversion on chromosome 7D linked to early heading and an QTL on chromosome 6D for the semi-dwarf phenotype Dw6. Intriguingly, they showed that synthetic-derived oat lines exhibiting extensive genomic rearrangements maintained strong agronomic performance, suggesting that such variation is not detrimental but potentially advantageous. As oat research enters the pangenomic era, these variations form another resource for precision breeding and the sustainable improvement of crop. (Summary by Ching Chan @ntnuchanlab) Nature 10.1038/s41586-025-09676-7