A SIMPLE AND OBJECTIVE APPROACH TO IDENTIFYING HUMAN ROUND SPERMATIDS

Although round spermatids have been studied extensively using staining techniques and electron microscopy, little information is available a bout their appearance in living conditions. We describe a method of co llecting and identifying round spermatids from ejaculates and testicul ar biopsies. The validity of the selection procedure was confirmed, by fluorescence in-situ hybridization. Based on cell size, morphological characteristics of nucleus and cytoplasm, and on the nucleus/cytoplas m ratio, we harvested a population of cells that was 84% haploid. This procedure can be applied to select spermatids for clinical or researc h purposes.