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Updated: Jun 25, 2026

FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
Partial chromosome deletion: a new trisomy rescue mechanism?
F Vialard1, D Molina-Gomes, E Quarello
1Department of Cytogenetics, CHI Poissy-St-Germain, Poissy, France. fvialard@hotmail.com
Objective:
We described a first case of a fetus with multiple congenital malformations associated with full trisomy 5 on direct CVS analysis and a partial trisomy 5 after cell culture.
Methods:
CVS karyotype (direct examination and culture) was performed after ultrasound examination and genetic counseling.
Results:
Direct CVS preparation showed a female karyotype with a homogeneous entire chromosome 5 trisomy, and karyotype of cultured CVS showed partial chromosome 5 trisomy, with an extra chromosome resulting from a deleted chromosome 5: 47,XX,del(5q31),+5. Only macroscopic examination could be performed because parents decided against postmortem examination and further analysis.
Conclusion:
After a brief literature review, we argue that all de novo large chromosome deletions need to be considered as potentially associated with a trisomy rescue and uniparental disomy.
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