These data shed light onto potentially relevant physiological differences between right and left atria: Our hypothesis-free analysis identified Pitx2c, a gene that has recently been shown to be involved in the pathophysiology of atrial fibrillation, as the single most enriched gene in the left atrium, while Bmp10, a gene known to be relevant for trabeculation of the right atrium and ventricle, was the single most differentially expressed gene in the right atrium. Here, BMP10 is linked to atrial fibrillation.