Answer:
Blood-cell cancer that begins in the bone marrow.
Explanation:
Chronic myeloid leukemia is caused by a rearrangement (translocation) of genetic material between chromosome 9 and 22. This translocation, written as t(9;22), fuses part of the ABL1 gene from chromosome 9 with part of the BCR gene from chromosome 22, creating an abnormal fusion gene called BCR-ABL1.