Experimental demonstration that mammalian oocytes are not selective towards X- or Y-bearing sperm
Article first published online: 24 MAR 2005
Copyright © 2005 Wiley-Liss, Inc.
Molecular Reproduction and Development
Volume 71, Issue 2, pages 245–246, June 2005
How to Cite
Zuccotti, M., Sebastiano, V., Garagna, S. and Redi, C. A. (2005), Experimental demonstration that mammalian oocytes are not selective towards X- or Y-bearing sperm. Mol. Reprod. Dev., 71: 245–246. doi: 10.1002/mrd.20252
- Issue published online: 24 MAR 2005
- Article first published online: 24 MAR 2005
- Manuscript Accepted: 10 NOV 2004
- Manuscript Received: 21 OCT 2004
- COFIN 2003
- Fondazione CARIPLO
- Istituto Superiore di Sanita'. Grant Number: CS17
- Ricerca Finalizzata Ministeriale 2002, Millipore
Mammalian oocytes are thought to be neutral as for X- or Y-bearing sperm selection is concerned, and penetration of an oocyte by an X- or a Y-bearing sperm is considered a random event. This assumption is mainly based on a posteriori evidences of a nearly equal sex ratio at birth, but it has never been experimentally demonstrated. We have designed a simple experiment, which allowed the penetration of an oocyte by more than one sperm and the further sexing by PCR of each single pronucleus present within the ooplasm. For the first time, we provide experimental evidence that mammalian oocytes do not play a selecting role since a single oocyte may be simultaneously fertilised by both X- and Y-bearing sperm. Mol. Reprod. Dev. 71: 245–246, 2005. © 2005 Wiley-Liss, Inc.