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Updated: Jul 28, 2026
07:57
Fish Sperm Assessment Using Software and Cooling Devices
Published on: July 28, 2018
Polyploidy in large-headed sperm: FISH study of three cases
F Devillard1, C Metzler-Guillemain, R Pelletier
1Laboratoire de Cytogénétique, Biologie de la Reproduction et CECOS, Centre Hospitalo-Universitaire de Grenoble, 38043 Grenoble cedex 09, France.
Human Reproduction (Oxford, England)
|May 1, 2002
Summary
Large-headed sperm with multiple tails, a rare cause of male infertility, show significant chromosomal abnormalities. These sperm defects suggest issues in cell division, posing risks for assisted reproduction.
Area of Science:
- Reproductive Biology
- Human Genetics
- Sperm Morphology
Background:
- Macrocephalic sperm with multiflagella is a rare condition linked to male infertility.
- Sperm chromosomal abnormalities may underlie this specific morphological defect.
Observation:
- Cytogenetic analysis of large-headed sperm was performed using fluorescence in-situ hybridization.
- Three patients with this specific sperm abnormality were included in the study.
Findings:
- Nearly all sperm analyzed contained at least one sex chromosome copy.
- Over half of the sperm exhibited extra copies of chromosome 1 or 18.
- Some sperm displayed tetraploidy, indicating significant chromosomal errors.
Implications:
- Meiotic divisions I and II appear affected, leading to abnormal chromosome segregation and nuclear cleavage.
- A direct correlation exists between this sperm morphology and abnormal cytogenetic content.
- Intracytoplasmic sperm injection (ICSI) may be ineffective and carry high genetic risks for affected individuals.
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