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Maternal origin of monosomy 21 derived from ICSI
S Ma1, W Robinson, R Lam
1Department of Obstetrics and Gynecology, University of British Columbia, Vancouver, Canada. sai@unixg.ubc.ca
Human Reproduction (Oxford, England)
|June 2, 2001
Summary
Intracytoplasmic sperm injection (ICSI) may pose genetic risks. A case study found monosomy 21 in a pregnancy conceived via ICSI, though the error likely occurred during egg formation, not ICSI itself.
Area of Science:
- Human Reproduction
- Clinical Genetics
- Assisted Reproductive Technology
Background:
- Intracytoplasmic sperm injection (ICSI) is increasingly used worldwide.
- Concerns exist regarding potential genetic risks associated with ICSI.
- Specifically, the possibility of ICSI facilitating the transmission of genetic defects to offspring is a key area of investigation.
Observation:
- ICSI was performed using spermatozoa from testicular sperm extraction (TESE) in a patient with azoospermia.
- The resulting pregnancy spontaneously aborted at 8 weeks gestation.
- Cytogenetic analysis of the aborted fetus revealed monosomy 21.
Findings:
- Molecular analysis confirmed the paternal origin of the single chromosome 21.
- The chromosomal segregation error leading to monosomy 21 was likely related to oogenesis (egg formation).
- However, the potential role of ICSI in fertilizing an abnormal oocyte cannot be entirely ruled out.
Implications:
- This case highlights the importance of ongoing surveillance for genetic abnormalities in pregnancies conceived via ICSI.
- While the direct link to ICSI is uncertain, the rarity of monosomy 21 warrants further research into assisted reproductive technologies and their genetic outcomes.
- Further studies are needed to fully elucidate the genetic safety profile of ICSI, particularly in cases involving male factor infertility.
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