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Updated: May 17, 2026
08:48
Flow Cytometric Analysis of Biomarkers for Detecting Human Sperm Functional Defects
Published on: April 21, 2022
CASA derived human sperm abnormalities: correlation with chromatin packing and DNA fragmentation
T Sivanarayana1, Ch Ravi Krishna, G Jaya Prakash
1Genetics Department, Krishna IVF Clinic, Krishna Nagar, Visakhapatnam, 530 002, Andhra Pradesh, India.
Journal of Assisted Reproduction and Genetics
|November 9, 2012
Summary
Specific abnormal sperm shapes are linked to poorer DNA quality. Selecting against these forms during intracytoplasmic sperm injection (ICSI) may improve assisted reproductive technology (ART) outcomes.
Area of Science:
- Reproductive Biology
- Andrology
- Genetics
Background:
- Sperm quality is crucial for successful fertilization.
- Chromatin integrity and DNA fragmentation are key indicators of sperm health.
- Intracytoplasmic sperm injection (ICSI) is a widely used assisted reproductive technology (ART).
Purpose of the Study:
- To investigate the relationship between abnormal sperm morphology and DNA integrity.
- To assess the impact of sperm chromatin abnormalities on ICSI outcomes.
- To evaluate the potential benefits of sperm selection in improving ART success rates.
Main Methods:
- Analysis of semen samples from 1002 patients using Computer-Assisted Sperm Analysis (CASA).
- Assessment of sperm morphology, motility, protamine status (chromomycin A3 staining), and DNA fragmentation (sperm chromatin dispersion assay).
Main Results:
- Abnormal sperm forms (elongated, thin, round, pyriform, amorphous, micro, macro) were significantly more prevalent in teratozoospermic and oligoasthenoteratozoospermic groups.
- Significant differences in chromatin packing and DNA fragmentation index were observed in abnormal sperm groups compared to normal.
- A significant correlation was found between abnormal motility parameters and DNA fragmentation index in the asthenozoospermic group.
Conclusions:
- Certain abnormal sperm morphological forms are associated with increased chromatin packing abnormalities and DNA fragmentation.
- The use of sperm with these abnormalities in ICSI may negatively affect fertilization, embryo development, and abortion rates.
- Selective avoidance of morphologically abnormal sperm during ICSI could enhance ART outcomes.
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