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Updated: Jul 17, 2026
07:34
FISH for Pre-implantation Genetic Diagnosis
Published on: February 24, 2011
Structural chromosomal mosaicism and prenatal diagnosis.
E Pipiras1, C Dupont, S Chantot-Bastaraud
1Service d'Histologie Embryologie Cytogénétique BDR, Hôpital Jean Verdier, Bondy, France.
Prenatal Diagnosis
|February 20, 2004
Summary
This study reports a rare case of prenatal chromosomal mosaicism, where a fetus had a partial trisomy 2p due to a translocation on chromosome 15. This condition presented with growth retardation and characteristic dysmorphic features.
Area of Science:
- Prenatal diagnostics
- Human genetics
- Cytogenetics
Background:
- True structural chromosomal mosaicism is uncommon in prenatal diagnosis, posing diagnostic and prognostic challenges.
- Accurate identification of chromosomal abnormalities is crucial for genetic counseling and management.
Observation:
- A fetus presented with a rare chromosomal abnormality: a translocation of chromosome 2p onto the short arm of chromosome 15 in 10% of cells, alongside a normal cell line.
- The fetal karyotype was identified as 46,XX,add(15)(p10).ish t(2;15)(p10;q10)(WCP2+)[3]/46,XX[27].
Findings:
- Post-termination examination of the fetus revealed growth retardation.
- The fetus exhibited dysmorphic features including dolichocephaly, hypertelorism, high forehead, low-set ears with prominent anthelix, and a small nose, consistent with partial trisomy 2p.
Implications:
- This case highlights the diagnostic complexities of prenatal mosaicism involving structural chromosomal rearrangements.
- Understanding the etiology of such rare events is vital for improving prenatal genetic counseling and prognostic assessments.
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