To investigate whether KCNN1 has a specificity for EwS over the alternative primary bone sarcoma in this age group, osteosarcoma, we performed RT-qPCR examining a larger panel of EwS cell lines (SK-ES-1, A673, TC-71, 5838, TTC-466 and CADO) and compared KCNN1 expression to the osteosarcoma cell lines HOS, SAOS and ZK-58 (Figure 2A). The gene discussed is KCNN1; the disease is osteosarcoma.