A recent study by Farnsworth et al, testing BNP vs NT-proBNP on 3,029 patients showed low diagnostic concordance between the two markers at their current cut-offs for HF (100 vs 300 pg/mL for BNP and NT-proBNP, respectively), and concordance was further decreased by renal disease [112]. The gene discussed is NPPB; the disease is hydrops fetalis.