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Sperm DNA fragmentation: causes and identification

Published online by Cambridge University Press:  11 October 2019

Thais Rose dos Santos Hamilton Open the ORCID record for Thais Rose dos Santos Hamilton [Opens in a new window]  and
Mayra Elena Ortiz D’Ávila Assumpção Open the ORCID record for Mayra Elena Ortiz D’Ávila Assumpção [Opens in a new window]
Thais Rose dos Santos Hamilton
Affiliation:
Animal Reproduction Department, School of Veterinary Medicine and Animal Science, University of São Paulo, SP, Brazil. Av. Prof. Dr. Orlando Marques de Paiva, 87, São Paulo, SP. CEP 05508-270, Brazil
Mayra Elena Ortiz D’Ávila Assumpção*
Affiliation:
Animal Reproduction Department, School of Veterinary Medicine and Animal Science, University of São Paulo, SP, Brazil. Av. Prof. Dr. Orlando Marques de Paiva, 87, São Paulo, SP. CEP 05508-270, Brazil
*
Author for correspondence: Mayra Elena Ortiz D’Ávila Assumpção. Animal Reproduction Department, School of Veterinary Medicine and Animal Science, University of São Paulo, SP, Brazil. Av. Prof. Dr. Orlando Marques de Paiva, 87, São Paulo, SP. CEP 05508-270, Brazil. Tel: +55 11 30917916. E-mail: meoaa@usp.br
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Summary

Sperm DNA fragmentation is referred to as one of the main causes of male infertility. Failures in the protamination process, apoptosis and action of reactive oxygen species (ROS) are considered the most important causes of DNA fragmentation. Action of ROS or changes in sperm protamination would increase the susceptibility of sperm DNA to fragmentation. Routine semen analysis is unable to estimate sperm chromatin damage. Sperm DNA integrity influences sperm functional capability, therefore tests that measure sperm DNA fragmentation are important to assess fertility disorders. Actually, there is a considerable number of methods for assessing sperm DNA fragmentation and chromatin integrity, sperm chromatin stability assay (SCSA modified), sperm chromatin dispersion (SCD), comet assay, transferase dUTP nick end labelling (TUNEL); and protamine evaluation in sperm chromatin assay, such as toluidine blue, CMA3, protamine expression and evaluation of cysteine radicals. This review aims to describe the main causes of sperm DNA fragmentation and the tests commonly used to evaluate sperm DNA fragmentation.

Keywords

DNA damageProtamineReactive oxygen speciesSperm chromatinSperm DNA evaluation
Type
Review Article
Information
Zygote , Volume 28 , Issue 1 , February 2020 , pp. 1 - 8
Copyright
© Cambridge University Press 2019 

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