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Updated: Nov 6, 2025
07:34
FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
37.4K
Reproductive outcomes in individuals with chromosomal reciprocal translocations
Angela Verdoni1, Jie Hu1, Urvashi Surti2
1Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA, USA.
Summary
Reciprocal balanced translocations (RBT) increase risks for pregnancy loss and infertility. Female gender, age, and prior pregnancy loss impact assisted reproductive technology success in RBT patients.
Area of Science:
- Reproductive genetics
- Human cytogenetics
Background:
- Reciprocal balanced translocations (RBT) are associated with recurrent pregnancy losses (RPL), infertility, and affected offspring.
- Current genetic counseling for RBT relies on products of conception (POC) karyotypes, with limited understanding of factors affecting assisted reproductive technologies (ART) success.
Purpose of the Study:
- To evaluate factors influencing ART success in couples with RBT.
- To establish risk elements for adverse reproductive outcomes in RBT patients.
Main Methods:
- Cytogenetic analysis of 261 POC and offspring from RBT-carrying parents.
- Assessment of chromosome segregation modes and euploid embryo rates in couples undergoing in vitro fertilization (IVF).
Main Results:
- Translocations involving acrocentric chromosomes increase the risk of unbalanced gametes via 3:1 segregation.
- Female RBT patients exhibit a higher risk of aneuploidy due to interchromosomal effects.
- Low euploid embryo rates result from RBT meiosis I malsegregation, meiosis II nondisjunction, and additional aneuploidies. RPL patients with RBT have increased miscarriage rates of euploid fetuses.
Conclusions:
- Chromosome-specific factors, female gender, age, and RPL history are key risk factors for pregnancy and IVF success in RBT patients.
- Chromosomal microarray analysis of POC is crucial for accurate diagnosis in patients with adverse reproductive outcomes.
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