Indeed, previous studies have revealed that SAC hyperactivation, for example by overexpression of another SAC component, MAD2, or by knocking down p31, a component of SAC silencing, could also induce CIN and cell death.[17, 39, 61, 62] Here we revealed that in the YY2‐induced SAC‐hyperactivated cell population, dying cells had significantly higher CIN than living cells, thus provides evidence that high CIN induces cell death and is thus deleterious for tumor cells. The gene discussed is YY2; the disease is neoplasm.