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Updated: Jun 2, 2026
07:34
FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
Unbalanced reciprocal translocations at amniocentesis.
Chih-Ping Chen1, Pei-Chen Wu, Chen-Ju Lin
1Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan. cpc_mmh@yahoo.com
Taiwanese Journal of Obstetrics & Gynecology
|April 13, 2011
Summary
Unbalanced reciprocal translocations detected during prenatal diagnosis often show fetal ultrasound abnormalities. This diagnosis can reveal balanced translocations within families, highlighting the need for parental genetic analysis.
Area of Science:
- Genetics
- Prenatal Diagnosis
- Cytogenetics
Background:
- Unbalanced reciprocal translocations are significant chromosomal abnormalities.
- Amniocentesis is a key diagnostic tool for prenatal genetic analysis.
- Understanding translocation segregation is crucial for genetic counseling.
Purpose of the Study:
- To detail perinatal outcomes of unbalanced reciprocal translocations found via amniocentesis.
- To analyze how these translocations are identified (ascertainment).
- To describe the patterns of chromosome segregation in affected fetuses.
Main Methods:
- Retrospective analysis of 40 cases diagnosed with unbalanced reciprocal translocations via amniocentesis.
- Data collected between January 1987 and July 2010 at Mackay Memorial Hospital.
- Review of perinatal findings, ascertainment modes, and segregation patterns.
Main Results:
- 82.5% of cases exhibited fetal ultrasound abnormalities.
- Adjacent-1 2:2 segregation was the most common mode (90%).
- 75.9% of translocations were inherited, with many families unaware of parental carrier status.
Conclusions:
- Abnormal ultrasound findings frequently accompany unbalanced translocations detected prenatally.
- Prenatal detection can uncover previously unknown balanced translocations in parents.
- Fetal structural abnormalities warrant cytogenetic investigation of the fetus and parents.
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