Bulk RNA-seq of 54 KAFOs (19 AF samples; 18–34 weeks GA) showed expression of canonical developmental renal epithelial and nephron progenitor genes (PAX2, PAX8, LHX1 and JAG1), while lacking cap mesenchyme markers (SIX2, CITED1 and GDNF). This evidence concerns the gene PAX8 and atrial fibrillation.