Jumping translocation: an unusual cytogenetic finding in myeloid neoplasm

Keywords:
cytogenetic; Jumping translocation; karyotype

Bone marrow karyotype of 86-year-old woman with myelofibrosis evolution from essential thrombocythemia showed unbalanced translocation involving chromosome 1 and acrocentric chromosomes 14, 15 and 22 (Figure 1), configuring the phenomenon of Jumping translocation (JT). Twenty metaphases showed: 46,XX,der(14)t(1;14)(q12;p11.2)[11]/46, XX,der(22)t(1;22)(q12;p11.2)[3]/46,XX,der(15)t(1;15)(q12;p11.2) [2]/46,XX[4].

Figure 1
A-G- banding Karyotype, showing ideogram of 1q in blue, 14q in yellow, 15q in red and 22q in green. B-Partial Karyo-type with normal chromosome 14, der(14)t(1;14)(q12;p11.2) and schematic model blue/yellow of der(14). C- Partial Karyotype with normal chromosome 15, der(15)t(1;15)(q12;p11.2) and schematic model blue/red of der(15). D- Partial Karyotype with normal chromosome 22, der(22)t(1;22)(q12;p11.2) and schematic model blue/green of der(22).

JT is a rare cytogenetic aberration that occurs when a donor segment chromosome breaks off and merges into two or more receptor chromosomes, resulting in an unbalanced translocation with gain of the donor chromosome segment.¹ This phenomenon shows genetic instability, despite not being associated with other chromosomal abnormalities and is associated with an unfavorable prognosis in myeloid neoplasms.² Among the chromosomal gains, the most frequent is the partial trisomy 1q, as in the case described.

REFERENCES

• ¹
  Coulture T, Amato K, DiAdamo A, Li P. Jumping Translocation of 1q in Myelodisplastic Syndrome and Acute Myeloid Leukemia: Report of three Cases and Review of Literature. Case Rep Genet. 2018;2018:8296478.
• ²
  Najfeld V, Tripodi J, Scalise A, Silverman LR, Silver RT, Fruchtman S, et al. Jumping translocations of the long arms of chromosome 1 in myeloid malignancies is associated with a high risk of transformation to acute myeloid leukaemia. Br J Haematol. 2010;151(3):288–91.

Publication Dates

• Publication in this collection
  12 Dec 2022
• Date of issue
  2022

History

• Received
  16 Mar 2021
• Accepted
  07 June 2021
• Published
  14 July 2021