Co-occurrence of TREX1 gain with 3q gain was observed in  ≥ 70% of CESC, CHOL, DLBC, KIRP, LAML, OV (ovarian serous adenocarcinoma), PAAD, and UCS samples, even though some of these tumor categories had very few TREX1 copy number gain events. The gene discussed is TREX1; the disease is ovarian serous adenocarcinoma.