Bcr gene is an abbreviation for the Breakpoint Cluster Region gene, located on human chromosome 22, and represents a fundamental concept in molecular biology and cancer research. It is primarily investigated for its critical involvement in recurrent chromosomal translocations, most notably the t(9;22) translocation that fuses it with the ABL1 gene from chromosome 9, resulting in the oncogenic BCR-ABL1 fusion gene. Research on the bcr gene examines its normal cellular function, its role in the pathogenesis of chronic myeloid leukemia (CML) and other hematological malignancies, and its significance as a diagnostic marker and target for therapeutic intervention.