VIII.C.001

t(9;22)(q34;q11.2). Major rearrangement. G-banding. Classical form of the Ph chromosome translocation. Arrows point to the elongated derived chromosome 9 and shortened derived chromosome 22. The latter is the Philadelphia chromosome, now identified by the designation “Ph chromosome.”

VIII.C.002

t(9;22)(q34;q11.2). Major rearrangement. FISH. Probe for 9q34 (ABL) (red) and 22q11.2 (BCR) (green). (A) Normal interphase cell. Two red and two green signals. (B) Abnormal cell. One fused signal indicates the derived chromosome 22 (the Ph-chromosome with the BCR and ABL genes fused). One red and green signal represents the normal chromosome 9 and 22. A smaller red signal represents the remaining part of chromosome 9 (derived 9).

VIII.C.003

t(9;22)(q34;q11.2). Major rearrangement with the leftover ABL gene deleted on the derived chromosome 9. G-banding. The arrow indicates the foreshortened derived chromosome 22 (Ph chromosome) and the derived 9 with the leftover ABL gene deleted. (Compare to image VIII.C.1. The translocated piece of 22 is not apparent.). Major rearrangement with the leftover ABL gene deleted on the derived chromosome 9. G-banding. The arrow indicates the foreshortened derived chromosome 22 (Ph chromosome) and the derived 9 with the leftover ABL gene deleted. (Compare to image VIII.C.1. The translocated piece of 22 is not apparent.)

VIII.C.004

t(9;22)(q34;q11.2). Major rearrangement with ABL leftover deleted. FISH. Probe for 9q34 (ABL gene) (red) and 22q11.2 (BCR gene) (green). (A) Normal interphase cell. Two chromosomes 9 (red signal) and two chromosomes 22 (green signal). (B) Abnormal cell. One red (normal chromosome 9) and green (normal chromosome 22) signal. One fused signal indicative of the derived chromosome 22 (Ph chromosome). Absence of a small red signal indicating the leftover ABL gene on the derived chromosome 9 is deleted (interphase preparation). (C) Abnormal cell. One red (normal chromosome 9) and green (normal chromosome 22) signal. One fused signal on the derived 22 indicative of Ph chromosome (metaphase preparation).