In a recent study, nine out of thirty nine mutated genes (23%) were involved in epigenetic regulation, with 34% of TCs exhibiting recurrent mutations in seven of them (BAP1, ASXL1, SETD2, SMARCA4, DNMT3A, TET2, and WT1), an observation which was not present for thymomas [15,23]. The gene discussed is SMARCA4; the disease is thymoma.