Reproduction, Fertility and Development Reproduction, Fertility and Development Society
Vertebrate reproductive science and technology
RESEARCH ARTICLE

Founders’ Lecture. Human spermatozoa: fruits of creation, seeds of doubt

R. John Aitken

ARC Centre of Excellence in Biotechnology and Development and Reproductive Science Group, Discipline of Biological Sciences, University of Newcastle, NSW 2308, Australia. email: jaitken@mail.newcastle.edu.au

Reproduction, Fertility and Development 16(7) 655-664 https://doi.org/10.1071/RD04083
Submitted: 2 August 2004  Accepted: 6 August 2004   Published: 21 September 2004

Abstract

Deoxyribonucleic acid damage in the male germline is associated with defective fertilisation, impaired embryonic development, reduced implantation, abortion and childhood disease. Oxidative stress and the retention of excess residual cytoplasm by the spermatozoa are frequently associated with the induction of such damage. The redox cycling of xenobiotics by oxido-reductases in the germline, the patient’s age, the incidence of genital tract infections and Sertoli cell dysfunction are all possible contributors to DNA damage in germ cells. Collateral peroxidation of unsaturated fatty acids in the sperm plasma membrane generally ensures that spermatozoa experiencing severe oxidative DNA damage cannot participate in the process of fertilisation. The adaptive termination of pregnancy through the selective vulnerability of genes involved in placentation may also help prevent the vertical transmission of damaged DNA. However, the ultimate safeguard against this form of damage will be to understand the biochemical basis of oxidative stress in human spermatozoa, so that the underlying causative mechanisms can be addressed in a logical manner.


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