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Updated: Aug 12, 2026

Chromosomics: Detection of Numerical and Structural Alterations in All 24 Human Chromosomes Simultaneously Using a Novel OctoChrome FISH Assay
06:25

Chromosomics: Detection of Numerical and Structural Alterations in All 24 Human Chromosomes Simultaneously Using a Novel OctoChrome FISH Assay

Published on: February 6, 2012

Complex chromosomal abnormalities in utero, 5 years before leukaemia

Zoë J Broadfield1, Richard D W Hain, Christine J Harrison

  • 1Leukaemia Research Fund Cytogenetics Group, Cancer Sciences Division, University of Southampton, Southampton, UK. zjb@soton.ac.uk

British Journal of Haematology
|July 20, 2004
PubMed

Insights

This study reports the first case of in utero development of ETV6/AML1-positive acute lymphoblastic leukemia (ALL) in identical twins. The findings suggest prenatal gene rearrangement and metastasis between twins, with a prolonged preleukaemic phase.

Area of Science:

  • Pediatric Oncology
  • Cancer Genetics
  • Hematology

Background:

  • Prenatal acquisition of gene rearrangements linked to leukemia is known.
  • ETV6/AML1 fusion is a common genetic alteration in childhood acute lymphoblastic leukemia (ALL).

Purpose of the Study:

  • To report the first case of a complex cytogenetic clone with ETV6/AML1 fusion developing in utero.
  • To investigate the prenatal origin and transmission of leukemia in identical twins.

Main Methods:

  • Karyotyping and interphase fluorescence in situ hybridization (FISH) were used.
  • Analysis of identical twin girls diagnosed with ALL.

Main Results:

  • Identical twin girls developed ETV6/AML1-positive ALL within months of each other.
  • Both twins shared an identical four-way variant t(12;21) chromosomal rearrangement.
  • Evidence suggests prenatal development, clonal expansion, and metastasis between twins.
  • A prolonged preleukaemic phase was observed in both children.

Conclusions:

  • The ETV6/AML1 fusion and complex chromosomal rearrangements likely occurred in utero.
  • Metastasis of abnormal cells from one twin to the other is a plausible transmission route.
  • The findings highlight the potential for prenatal oncogenesis and a long preleukaemic phase in childhood ALL.

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