Final analyses showed that PINP (PIN, r = 0.423 > PICP, r = 0.386) and TGF-β1 (TGF-β1, r = 0.469 > PIIINP, r = 0.291) were sensitive fibrosis biomarkers for the left atria of AF patients, while PICP (PICP, r = 0.336 > TGF-β1, r = 0.258) was a sensitive fibrosis biomarker for the right atria. This evidence concerns the gene TGFB1 and atrial fibrillation.