Evaluation of aneuploidy and DNA damage in human spermatozoa: applications in field studies

Abstract

With the goal of incorporating measures of sperm nuclear integrity in an epidemiology study, semen samples from young Czech men were analysed for sperm aneuploidy and sperm chromatin structure in addition to routine measures of sperm production and quality. The exposure in question was to high seasonal air pollution containing reactive polyaromatic hydrocarbons potentially capable of affecting spermatogenesis and damaging sperm DNA. The sperm aneuploidy assay uses fluorescence in situ hybridization to label selected sperm chromosomes; as applied in this study, the sex chromosomes (X,Y) and chromosome 8 were targeted. The sperm chromatin structure assay detects sperm nuclei with increased susceptibility to denaturation, a feature that is associated with DNA damage. Logistically, these assays were relatively easy to incorporate into the study design. The aneuploidy assay provided information suggesting that exposure to high levels of air pollution may increase the risk of sperm aneuploidy and that it is important to control for exposure to cigarette smoke and/or alcohol in such studies. The sperm chromatin structure assay provided valuable baseline information about Czech semen donors and data suggestive of an adverse effect of smoking and air pollution on spermatozoa that merits further investigation.

A comparison of alternative assays to measure DNA damage in stallion spermatozoa: TUNEL test versus ‘Nicoletti assay’

“…Some other authors have also found false positive results with the TUNEL test on various cell types including liver and kidney cells (Stahelin et al, 1998;Pulkkanen et al, 2000). The sensitivity and the selectivity of the assay have also been criticised; moreover, many variants exist and there are no conventional rules on how to carry out the test and evaluate the results (Perreault et al, 2000). The false positive results of TUNEL indicate that conventional flow cytometers are not able to locate the origin of the signal, so fluorescent microscopic control of the results should be a necessary step in every experiment to avoid the interpretation of false data.…”

Off to a good start: the influence of pre- and periconceptional exposures, parental fertility, and nutrition on children's health.

“…Previous studies that have tried to establish cause-effect relationships by evaluating DNA quality of sperm after the birth of an abnormal child have not been successful because of this temporal flaw. Recent advances in molecular-cell and genetic laboratory techniques now allow sophisticated assessment of human sperm DNA and chromatin damage (Evenson et al 2002;Perreault et al 2000Perreault et al , 2003. There are new understandings of the critical role of sperm chromatin organization and paternal DNA in early embryo development (Evenson 1999;Sakkas et al 1998;Tesarik et al 2002).…”

The value of home-based collection of biospecimens in reproductive epidemiology.

“…In addition to measuring biochemical components of the semen, one can conduct routine sperm analysis (concentration, motility, morphology) (Davis and Katz 1989;WHO 1999), evaluate more specific markers of sperm function such as genetic and chromosome integrity (Evenson et al 2002;Perreault et al 2000), and conduct gene expression profiling experiments (Ostermeier et al 2002).…”