Frequency of heterozygous TET2 deletions in myeloproliferative neoplasms

Figures & data

Table 1 Interphase FISH detection of TET2 deletion

	PMF	PV	ET	MPNu	MPNu/MDS	Total
Cytogenetics
Normal	15	14	6	8	1	44
Abnormal	25	8	2	2	2	39
ND	12	25	13	10	3	63
Total	52	47	21	20	6	146
JAK2 status
JAK2V617F	4	16	9	0	0	29
JAK2 wt	6	1	5	0	0	12
ND	42	30	7	20	6	105
Total	52	47	21	20	6	146
MPL status
MPLW515L	0	1	1	0	0	2
MPL wt	2	4	7	0	0	13
ND	50	42	13	20	6	131
Total	52	47	21	20	6	146
TET2 status
TET2+	2	0	0	0	0	2
TET2−	50	47	21	20	6	144
Total	52	47	21	20	6	146

Notes: (+) deletion; (−) I-FISH did not detect deletion of three bacterial artificial chromosomes.

Abbreviations: FISH, fluorescence in situ hybridization; MPNu, myeloproliferative neoplasm (unclassified); ND, not done; wt, wild type; MDS, myelodysplastic syndrome; ET, essential thrombocythemia; PV, polycythemia vera; PMF, primary myelofibrosis.

Table 2 Summary of results from two patients with TET2 deletions

Pt #	Dx	Mutational status		TET2 BACs			% of nuclei	Karyotype
		JAK2V617F	MPLW515L	RP11-912N16	RP11-16G16	RP11-45L9
8	PMF	+	ND	+	−	+	90	46,XY
34*	PMF	+	ND	−	−	−	5	45,XY,-7,del(10) (q21),inv(12) (?p12.1;q13.3), der(12)t(12;?), add(17)(p11.24)

Notes: On a subsequent follow-up specimen a clone with the karyotype 45,XY,der(4)del(4)(p14)del(q24),-7,del(8)(p21)del(10)(q22),add(17)(p11.2),del(20(q11q13) had developed.

Abbreviations: ND, not done; PMF, primary myelofibrosis; BACs, bacterial artificial chromosomes.

Figure 1 Interphase nuclei representing TET2 FISH signal patterns. A) Normal nuclei with two triple color fusion signals. B) Deletion of the 175 kb RP11-16G16 BAC probe (aqua). C) Deletion of all three bacterial artificial chromosome probes; note only one triple color fusion signal.