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Updated: Jun 30, 2026
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Chromosomics: Detection of Numerical and Structural Alterations in All 24 Human Chromosomes Simultaneously Using a Novel OctoChrome FISH Assay
Published on: February 6, 2012
Extra structurally abnormal chromosomes (ESACs)--presentation of 10 new cases.
B Kałuzewski1, Z Helszer, M Constantinou
1Division of Genetics, Department of Medical Genetics, Medical University of Łodź, ul. Sterlinga 1/3, 91-425 Łódź, Poland. genetyka@am.psk2.lodz.pl
Summary
Classical banding techniques remain valuable for diagnosing extra small supernumerary marker chromosomes (ESACs) and understanding their genetic activity. These cytogenetic methods aid in prognosing outcomes for individuals with these chromosomal abnormalities.
Area of Science:
- Cytogenetics
- Human Genetics
- Medical Diagnostics
Background:
- Retrospective reliability assessment of classical banding cytogenetic studies.
- Prognosing epicrises in 14 cases with additional marker chromosomes.
- Evaluating the diagnostic utility of cytogenetic techniques for marker chromosomes.
Observation:
- 14 cases (0.2%) of extra small supernumerary marker chromosomes (ESACs) diagnosed in 6875 individuals.
- DA/DAPI(+) inv dup (15) observed in 5 cases, with polymorphic bands correlating to pathological signs.
- Bisatellite heterochromatic ESACs identified in 6 cases using NOR and CBG banding techniques.
Findings:
- Classical banding techniques successfully identified and characterized various types of ESACs.
- Replication banding techniques revealed 'genetic activity' or 'inactivity' of marker chromosomes.
- The size of polymorphic bands on marker chromosomes correlated with the presence or absence of pathological signs.
Implications:
- Classical and replication banding techniques are still relevant despite advancements in molecular methods.
- These cytogenetic techniques provide crucial insights into DNA replication kinetics at the band level.
- Reliable cytogenetic analysis aids in accurate diagnosis and prognosis for individuals with chromosomal abnormalities.
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