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Updated: Jul 15, 2026
16:19
Fluorescence in situ hybridization (FISH) Protocol in Human Sperm
Published on: September 1, 2009
Localization of single-stranded DNA in human sperm nuclei
Xiaoyang Zhang1, Maria San Gabriel, Jamie Libman
1Division of Urology, Department of Surgery, Royal Victoria Hospital, McGill University, Montreal, Quebec, Canada.
Fertility and Sterility
|April 25, 2007
Summary
Infertile men show more sperm with diffuse single-stranded DNA (ssDNA) in their nuclei compared to fertile men. This suggests diffuse ssDNA staining indicates abnormal spermatozoa, impacting male fertility.
Area of Science:
- Reproductive Biology
- Spermatozoa DNA Integrity
- Male Infertility Research
Background:
- Sperm nuclear DNA integrity is crucial for male fertility.
- Single-stranded DNA (ssDNA) foci in sperm nuclei are not well understood.
- Identifying markers of sperm abnormality can aid infertility diagnosis.
Purpose of the Study:
- To investigate the presence and localization of single-stranded DNA (ssDNA) within sperm nuclei.
- To compare ssDNA distribution patterns in spermatozoa from fertile and infertile men.
- To determine if ssDNA patterns correlate with male infertility.
Main Methods:
- Prospective observational study conducted at a university infertility clinic.
- Semen samples analyzed from 12 infertile men (asthenoteratospermia) and 5 fertile men.
- Immunocytochemistry using an ssDNA-targeting antibody was employed to visualize ssDNA patterns.
Main Results:
- Two distinct sperm nuclear staining patterns for ssDNA were observed: faint punctated and diffuse.
- Infertile men exhibited a significantly higher proportion of spermatozoa with diffuse ssDNA staining (52% ± 19%) compared to fertile men (14% ± 13%).
- Diffuse ssDNA staining was more prevalent in whole semen samples than in processed samples.
Conclusions:
- Human sperm nuclei typically display discrete, likely peripheral, foci of ssDNA.
- A higher prevalence of diffuse ssDNA in sperm nuclei is associated with male infertility.
- Diffuse nuclear ssDNA staining in spermatozoa is indicative of abnormality and potential infertility.
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