Ws-2 Introgression in a Proportion of Arabidopsis thaliana Col-0 Stock Seed Produces Specific Phenotypes and Highlights the Importance of Routine Genetic Verification

Arabidopsis thaliana is an important model organism with a robust network of resources that has been of enormous value to the plant science research community. The use of isogenic material as a reference point or control is critical for many types of experiments in plant molecular biology and genetics. Recently, we noticed that some seed from a common source of the widely used Columbia-0 (Col-0) strain gave rise to plants showing features atypical for this strain. Whole-genome DNA-sequencing and allele-specific PCR assays confirmed that the abnormal individuals contain multiple introgressions from the ecotype Wassilewskija-2 (Ws-2), as described below. This emphasizes the importance of practices necessary to maintain the integrity of seed stocks and other biological collections. We urge research groups to evaluate whether they may have been affected and to revisit their materials if needed