Prochi F. Madon, Genetics Lab, 6th Floor, Dept. of Assisted Reproduction and Genetics, Jaslok Hospital and Research Centre, 15, Dr. G. Deshmukh Marg, Mumbai, Maharashtra 400026, India. , Madon Prochi F.1 , Shah Samir S.2 , Sanap Rupesh R.3 , Athalye Arundhati S.4 , Lele Hrushikesh M.5 , Parikh Rupali S.6 , Vaswani Lakshmi P.7 , Yargop Mamta V.8 , Parikh Firuza R.9
Context: Variants of standard translocations in leukemia are occasionally suspected initially by fluorescence in-situ hybridization (FISH), due to a different signal pattern. In many cases, this is due to the involvement of an additional chromosome, eading to a complex three-way translocation. If the breakpoints are in the telomeric region, the cryptic translocation may not be visible on karyotyping. We describe here the characterization of a variant AML1/ ETO fusion involving 6q in a patient with AML-M2 Aims: To identify and confirm the extra chromosome involved in a variant AML1/ETO translocation in a case of AML-M2.
Settings and Design: First routine FISH for AML1/ ETO and conventional karyotyping was carried out. Reflex FISH was set up on previously Giemsabanded metaphases in two rounds to confirm that chromosome 6 was additionally involved in the AML1/ETO translocation.
Material and Methods: Heparinized bone marrow aspirate was obtained from a suspected case of AML-M2. Cytogenetic analysis by routine FISH for AML1/ETO and conventional karyotyping was carried out. Reflex FISH was set up on Giemsabanded metaphases in two rounds using probes for AML1/ETO followed by CEP 6.
Results: FISH results showed the presence of a variant signal pattern for translocation AML1/ ETO. Karyotyping of Giemsa-banded metaphases showed suspicion of a three way translocation t (8;6;21) (q22.1;q27;q22.2) which was confirmed by reflex FISH analysis.
Conclusions: In cases with suspicion of a cryptic three way translocation, reflex FISH on previously Giemsa-banded metaphases gives a clue about the additional partner chromosome which can be different in each case.
No records found.
| Received | Accepted | Published |
|---|---|---|
| N/A | N/A | N/A |
Sunday 21 June 2026, 19:52:19 (IST)
Download citation
Highlight selected keywords in the article text.
| Received | N/A |
| Accepted | N/A |
| Published | N/A |