eLife assessment
This important study of mouse genetic variation in atrial septum formation, a trait correlated with the patent foramen ovale (PFO) cardiac defect, provides convincing evidence for 37 quantitative trait loci (QTL) affecting this trait, combining genetic mapping with transcriptome analysis to zero in on relevant pathways and candidate genes within the QTL, and validating the role of one gene in tissue culture. The paper provides an important resource for hypothesis generation and future studies, which could lead to novel diagnostic or therapeutic approaches that target atrial septal defects in common congenital heart disease.