WES also revealed a NPM1 mutation (type A19) at Dx, whose AF was decreased at Re (p = 8.2 × 10–3) and a low-abundant NRAS mutation at Dx (VAF = 0.087) that was undetected at Re (VAF = 0; p = 2.0 × 10–4; Fig. 1C). The gene discussed is NRAS; the disease is atrial fibrillation.