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Author Spotlight: Advancing Male Infertility Research by Unraveling Sperm Metabolism and Mitochondrial Function
Published on: June 23, 2023
Sperm mitochondrial DNA deletion in Iranian infertiles with asthenozoospermia
I Bahrehmand Namaghi1, H Vaziri1
1Department of Biology, Faculty of Sciences, University of Guilan, Rasht, Iran.
Abstract:
Asthenozoospermia is an important cause of male infertility. The mutations in sperm mitochondrial DNA (mtDNA) result in either functionless or malfunctioning some proteins, subsequently affecting sperm motility leading to asthenozoospermia. The purpose of this study was to investigate sperm mtDNA 4,977-bp deletion in infertile men with low sperm motility/immotile spermatozoa compared to healthy subjects with high sperm motility. Semen samples of 256 asthenozoospermic infertiles and 200 controls from northern Iran were collected. After extraction of spermatozoa total DNA, Gap-polymerase chain reaction (Gap-PCR) was performed. The deletion was observed in 85.93% of patients with asthenozoospermia compared with 14% in controls [OR = 37.5397, 95% confidence interval = 12.937-108.9276, p < .0001]. It is concluded that there is a strong association between sperm mtDNA 4,977-bp deletion and asthenozoospermia-induced infertility in the population examined. Large-scale mtDNA deletions in spermatozoa may induce bioenergetic disorders. Nevertheless, to validate our results broader research may be needed.
Insights
Sperm mitochondrial DNA (mtDNA) deletions are strongly linked to asthenozoospermia, a cause of male infertility. This study found the 4,977-bp deletion in 85.93% of infertile men with low sperm motility.
Area of Science:
- Reproductive Biology
- Genetics
- Male Infertility
Background:
- Asthenozoospermia, characterized by low sperm motility, is a significant factor in male infertility.
- Sperm mitochondrial DNA (mtDNA) mutations can impair protein function, affecting sperm motility and leading to asthenozoospermia.
Purpose of the Study:
- To investigate the prevalence of the sperm mtDNA 4,977-bp deletion in infertile men with asthenozoospermia.
- To compare the frequency of this deletion in infertile men versus healthy men with high sperm motility.
Main Methods:
- Semen samples were collected from 256 infertile men with asthenozoospermia and 200 healthy controls.
- Total DNA was extracted from spermatozoa.
- Gap-polymerase chain reaction (Gap-PCR) was used to detect the 4,977-bp deletion in sperm mtDNA.
Main Results:
- The 4,977-bp deletion was found in 85.93% of asthenozoospermic patients, significantly higher than the 14% observed in controls.
- A strong statistical association was found between the sperm mtDNA 4,977-bp deletion and asthenozoospermia-induced infertility (OR = 37.54, p < .0001).
Conclusions:
- There is a significant association between the sperm mtDNA 4,977-bp deletion and asthenozoospermia in the studied Iranian population.
- Large-scale mtDNA deletions in spermatozoa may lead to bioenergetic dysfunction, contributing to infertility.
- Further research is recommended to validate these findings in broader populations.
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