TBX1 overexpression correlated with genomic amplifications at 22q11 in the CML cell lines K-562 and TK-6, indicating a pathogenic connection to the hallmark fusion gene BCR::ABL1 and uncovering the oncogenic role of TBX1 in CML. The gene discussed is BCR; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.