This study uses diverse wheat accessions to map expression quantitative trait loci (eQTL) and evaluate their effects on population-scale variation in homoeolog expression dosage. The relative contribution of cis- and trans-eQTL is affected by selection and demographic events. Cis-acting variants largely influence homoeolog expression dosage and appear to be under selection. The frequency and expression of homoeologous gene alleles with strong expression dosage bias predict variation in yield-related traits, likely impacted by breeding. The study highlights the importance of genomic variants affecting homoeolog expression dosage in shaping agronomic phenotypes and their potential utility for yield improvement in polyploid crops.

Fei He, Wei Wang, William B. Rutter, Katherine W. Jordan, Jie Ren, Ellie Taagen, Noah DeWitt, Deepmala Sehgal, Sivakumar Sukumaran, Susanne Dreisigacker, Matthew Reynolds, Jyotirmoy Halder, Sunish Kumar Sehgal, Shuyu Liu, Jianli Chen, Allan Fritz, Jason Cook, Gina Brown-Guedira, Mike Pumphrey, Arron Carter, Mark Sorrells, Jorge Dubcovsky, Matthew J. Hayden, Alina Akhunova, Peter L. Morrell, Les Szabo, Matthew Rouse, Eduard Akhunov