Towards the development of a fluorescent in situ hybridization based genotoxicologic assay for aneuploidy detection in sperm.

Fluorescent in situ hybridization (FISH) is a molecular cytogenetic technique which allows an analysis of chromosome copy number in interphase cells. The cytological examination of spermatozoa is routinely performed as part of semen analysis. While this analysis is only a component of the evaluation of an infertile male, the aetiology of many cases of infertility remains unknown. FISH on semen smears can yield information on chromosome-specific aneuploidy due to constitutional and acquired chromosomal abnormalities as found with cancer or exposure to genotoxic substances. The ability to analyse germ cells directly is a useful adjunct to GTG-banding analysis of meiotic chromosomes, an invasive and extremely labour-intensive procedure. The work of 2 years in developing and optimizing a FISH-based assay in routinely processed semen smears is described.