De novo cytogenetic alterations in spermatozoa of subfertile males might be due to genome instability associated with idiopathic male infertility: Experimental evidences and Review of the literature<br>

Hossein Mozdarani; Sohail Mozdarani; Hossein Mozdarani; Sohail Mozdarani

doi:10.3934/genet.2016.4.219

AIMS Genetics

2016, Volume 3, Issue 4: 219-238. doi: 10.3934/genet.2016.4.219

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Research article

De novo cytogenetic alterations in spermatozoa of subfertile males might be due to genome instability associated with idiopathic male infertility: Experimental evidences and Review of the literature

Running title: Sperm cytogenetic alterations and male infertility

Hossein Mozdarani ^{1
,
,},
Sohail Mozdarani ²

1.
Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Ale-Ahmad Highway, Tehran, P.O.Box: 14115-111, Iran
2.
Cytogenome Medical Genetics Lab, Chamran Medical Building, Parvaneh St. Ale-Ahmad Highway, Tehran, Iran

Received: 04 September 2016 Accepted: 07 November 2016 Published: 16 November 2016

Male infertility is caused by many factors including genetics. Although part of genetic damages are inherited and could be traced in blood leukocytes, but those de novo alterations induced in spermatogenesis are not part of diagnostic work up. De novo alterations might be the cause of many idiopathic conditions of male infertility. The aim of this study was to evaluate DNA damage, sex chromosomal aneuploidy and DAZ microdeletion in sperms of subfertile males in comparison with normal healthy individuals. Whole blood and semen samples were obtained from 75 subfertile and 45 normal men. Semen samples from karyotypically normal subfertile and normal individuals were used for DNA fragmentation, sex chromosome aneuploidy and DAZ microdeletion analysis. Sperm DNA damage was assessed by alkaline comet assay, chromosome aneuploidy and DAZ microdeletion was assessed using a combined primed in situ labeling and fluorescent in situ hybridization (PRINS-FISH) method. A significantly high percentage of DNA fragmentation was observed in subfertile patients compared to control. Similar observation was observed for sex chromosome aneuploidy and DAZ microdeletion (p < 0.01). A relatively small interindividual difference was seen in all three assays performed. However DAZ microdeletion was observed as mosaic form in Y bearing sperms. Results indicate that subfertile males experience higher genome instability in spermatogenesis expressed as DNA damage and consequently sperm chromosomal aneuploidy or microdeletions. Occurrence of de novo genetic alterations caused by environmental chemico-physical genotoxic agents during spermatogenesis might be one of the causes of idiopathic male infertility.
- Subfertile male,
- idiopathic male infertility,
- genome instability,
- DNA damage,
- DAZ microdeletion
Citation: Hossein Mozdarani, Sohail Mozdarani. De novo cytogenetic alterations in spermatozoa of subfertile males might be due to genome instability associated with idiopathic male infertility: Experimental evidences and Review of the literature[J]. AIMS Genetics, 2016, 3(4): 219-238. doi: 10.3934/genet.2016.4.219

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Abstract

Male infertility is caused by many factors including genetics. Although part of genetic damages are inherited and could be traced in blood leukocytes, but those de novo alterations induced in spermatogenesis are not part of diagnostic work up. De novo alterations might be the cause of many idiopathic conditions of male infertility. The aim of this study was to evaluate DNA damage, sex chromosomal aneuploidy and DAZ microdeletion in sperms of subfertile males in comparison with normal healthy individuals. Whole blood and semen samples were obtained from 75 subfertile and 45 normal men. Semen samples from karyotypically normal subfertile and normal individuals were used for DNA fragmentation, sex chromosome aneuploidy and DAZ microdeletion analysis. Sperm DNA damage was assessed by alkaline comet assay, chromosome aneuploidy and DAZ microdeletion was assessed using a combined primed in situ labeling and fluorescent in situ hybridization (PRINS-FISH) method. A significantly high percentage of DNA fragmentation was observed in subfertile patients compared to control. Similar observation was observed for sex chromosome aneuploidy and DAZ microdeletion (p < 0.01). A relatively small interindividual difference was seen in all three assays performed. However DAZ microdeletion was observed as mosaic form in Y bearing sperms. Results indicate that subfertile males experience higher genome instability in spermatogenesis expressed as DNA damage and consequently sperm chromosomal aneuploidy or microdeletions. Occurrence of de novo genetic alterations caused by environmental chemico-physical genotoxic agents during spermatogenesis might be one of the causes of idiopathic male infertility.

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