| Phenotype / cell stem origin | Mainly cases of acute myeloid leukemia (AML) of various subtypes: M0 , M1, M2, M4, M5, M6, M7, and RAEB-t. Four cases of acute lymphoblastic leukemia (ALL) are reported. |
| Epidemiology | at least 29 cases known; the translocation may be overlooked, and therefore underestimated; was found in 3% of children cases of ANLL, that was also 15% of infant cases of ANLL under 18 mths; sex ratio 15M/14F, age : 0-24 mths (n= 29), median 7 mth (n=29) |
| Clinics | WBC range 8-230 x 109/L, median 12 x10 9/L; organomegaly, central nervous system involvement in 3 of 6 cases |
| Prognosis | probably poor prognosis: median survival is 13 months. Of 6 cases, one case had no remission and died at 7 mths; 4 case had relapse (duration first remission 1-20 mths), 2 cases are still alive (16 mths + and 33 mths +) |
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Left: example of FISH performed on bone marrow metaphase from a patient with t(7;12)(q36;p13). Dual colour FISH using whole chromosome paint specific for chromosome 7 (in green) and chromosome 12 (in red) shows the reciprocal translocation. The arrow indicates the der(7) and the arrowhead indicates the der(12) - Sabrina Tosi; Right: Example of double colour FISH performed on bone marrow metaphase from a patient with t(7;12)(q36;p13). The PAC clone 1121A15 for the breakpoint region at chromosome band 7q36 (in green) and a cosmid cocktail for ETV6 at chromosome band 12p13 (in red) show one green signal for the normal chromosome 7, one red signal for the normal chromosome 12 and two fusion signals at both the derivative chromosomes 7 and 12 - Anne RM von Bergh and H. Berna Beverloo. |
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| Cytogenetics Morphological | Not always visible by chromosome banding techniques alone; may also be misdiagnosed as del(12)(p13) |
| Cytogenetics Molecular | Detectable by dual colour FISH. A cosmid cocktail or YAC 964c10 shows a split signal on the der(12) and der(7). Also the commercial probe LSI TEL/AML1 (ES) for the detection of the t(12;21) shows a split signal on the der(7) and the der(12) in the t(7;12) cases since the breakpoint in these cases falls within the first three exons, which are contained in this probe. FISH using the PAC clone RP5-1121A15 mapping to 7q36 shows a split signal on the der(7) and der(12). |
| Probes | Chromosome 7 paint, wcp7 directly labelled with SpectrumGreen Chromosome 12 paint, wcp12 directly labelled with SpectrumOrange YAC 964c10 (CEPH, Paris) LSI TAL/AML1 (ES) PAC H_DJ1121A15 |
| Additional anomalies | +19 in 23 of 29 cases, +8 in 7 of 29 cases (+8,+19 in 6 cases) |
| Identification of new partner chromosomes involved in fusions with the ETV6 (TEL) gene in hematologic malignancies. |
| Tosi S, Giudici G, Mosna G, Harbott J, Specchia G, Grosveld G, Privitera E, Kearney L, Biondi A, Cazzaniga G |
| Genes, chromosomes & cancer. 1998 ; 21 (3) : 223-229. |
| PMID 9523197 |
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| Fluorescence in situ hybridization characterization of new translocations involving TEL (ETV6) in a wide spectrum of hematologic malignancies. |
| Wlodarska I, La Starza R, Baens M, Dierlamm J, Uyttebroeck A, Selleslag D, Francine A, Mecucci C, Hagemeijer A, Van den Berghe H, Marynen P |
| Blood. 1998 ; 91 (4) : 1399-1406. |
| PMID 9454771 |
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| Chromosome abnormalities and MLL rearrangements in acute myeloid leukemia of infants. |
| Satake N, Maseki N, Nishiyama M, Kobayashi H, Sakurai M, Inaba H, Katano N, Horikoshi Y, Eguchi H, Miyake M, Seto M, Kaneko Y |
| Leukemia : official journal of the Leukemia Society of America, Leukemia Research Fund, U.K. 1999 ; 13 (7) : 1013-1017. |
| PMID 10400416 |
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| t(7;12)(q36;p13), a new recurrent translocation involving ETV6 in infant leukemia. |
| Tosi S, Harbott J, Teigler-Schlegel A, Haas OA, Pirc-Danoewinata H, Harrison CJ, Biondi A, Cazzaniga G, Kempski H, Scherer SW, Kearney L |
| Genes, chromosomes & cancer. 2000 ; 29 (4) : 325-332. |
| PMID 11066076 |
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| t(7;12)(q36;p13) and t(7;12)(q32;p13)--translocations involving ETV6 in children 18 months of age or younger with myeloid disorders. |
| Slater RM, von Drunen E, Kroes WG, Weghuis DO, van den Berg E, Smit EM, van der Does-van den Berg A, van Wering E, Hˆ§hlen K, Carroll AJ, Raimondi SC, Beverloo HB |
| Leukemia : official journal of the Leukemia Society of America, Leukemia Research Fund, U.K. 2001 ; 15 (6) : 915-920. |
| PMID 11417477 |
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| Fusion of the homeobox gene HLXB9 and the ETV6 gene in infant acute myeloid leukemias with the t(7;12)(q36;p13). |
| Beverloo HB, Panagopoulos I, Isaksson M, van Wering E, van Drunen E, de Klein A, Johansson B, Slater R |
| Cancer research. 2001 ; 61 (14) : 5374-5377. |
| PMID 11454678 |
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| Heterogeneity of the 7q36 breakpoints in the t(7;12) involving ETV6 in infant leukemia. |
| Tosi S, Hughes J, Scherer SW, Nakabayashi K, Harbott J, Haas OA, Cazzaniga G, Biondi A, Kempski H, Kearney L |
| Genes, chromosomes & cancer. 2003 ; 38 (2) : 191-200. |
| PMID 12939747 |
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