A new ash pangenome is turning dieback resistance from a few markers into a much larger genetic landscape

Sequencing across diverse European ash captured structural variation missing from a single reference genome and recovered shared genetic signals associated with lower ash-dieback susceptibility.

Wild Lands Ecological Intelligence Editor
Wild Lands Institute · 20 September 2026

Evidence: Peer-reviewed
Geography: European ash populations, with extensive UK disease phenotyping
System: European ash forests and ash-dieback disease

WHAT THE EVIDENCE SAYS

A Nature Communications study built a pangenome from 50 diverse ash samples and identified hundreds of thousands of structural variants, including roughly 174 megabases of sequence absent from the previous linear reference. Reanalysis of more than 1,200 phenotyped trees identified hundreds of SNPs showing consistent allele-frequency shifts between healthy and heavily damaged trees across UK seed sources.

WHY IT MATTERS / OUR READ

Forest-disease adaptation is increasingly a genomic-screening problem as well as a silvicultural one. A richer reference can improve breeding and conservation of genetic diversity by revealing resistance-associated variation that a single genome can miss.

CAVEATS / UNCERTAINTY

The 50-sample pangenome cannot capture all rare structural variation, much of the disease phenotype comes from UK material, and association with lower susceptibility is not the same as a proven breeding response or durable resistance across environments.

SOURCE

Nature Communications
View original evidence ↗