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Updated: Aug 18, 2026

FISH for Pre-implantation Genetic Diagnosis
07:34

FISH for Pre-implantation Genetic Diagnosis

Published on: February 23, 2011

An unusual reciprocal translocation detected by subtelomeric FISH: interstitial and not terminal

Mariluce Riegel1, Alessandra Baumer, Jochen Süss

  • 1Institute of Medical Genetics, University of Zürich, Schorenstrasse 16, CH-8603 Schwerzenbach, Switzerland. riegel@medgen.unizh.ch

American Journal of Medical Genetics. Part A
|April 6, 2005
PubMed

Insights

This study investigates a child

Area of Science:

  • Genetics
  • Molecular Biology
  • Developmental Biology

Background:

  • Karyotype-phenotype correlation is crucial for understanding genetic disorders.
  • Chromosomal abnormalities can lead to a range of congenital anomalies and developmental issues.

Observation:

  • An 11-month-old boy presented with dysmorphic signs, congenital heart defects (atrial septal defect), inguinal hernia, undescended testes, urinary reflux, renal dysplasia, and developmental delay.
  • Initial karyotype revealed an abnormal chromosome 11 with additional material of unknown origin on the long arm.

Findings:

  • Maternal karyotype showed a translocation t(2;11)(q35;q24.2), initially suggesting a reciprocal exchange with 2q duplication and 11q deletion.
  • Subtelomeric fluorescence in situ hybridization (FISH) and microsatellite marker analysis revised the interpretation, indicating an unusual interstitial translocation and redefining the deleted and duplicated segments.

Implications:

  • The revised genetic findings necessitate a re-evaluation of the initial karyotype-phenotype correlation.
  • Accurate characterization of chromosomal breakpoints and segments is essential for genetic counseling and understanding disease mechanisms.

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