Higher levels of fibrotic biomarkers such as TGF-β1 and PIIINP are found to be associated with extensive myocardial fibrosis, especially atrial fibrosis, and may act as predictors for adverse outcomes such as AF recurrences after ablation or post-operative AF [2, 5, 6]. The gene discussed is TGFB1; the disease is atrial fibrillation.