Molecular mechanisms of gamete recognition and fusion at fertilization

Advances in many areas of reproductive technology have been rapid and, in many respects, have outstripped our knowledge of the fundamental processes of human and animal sperm-egg interactions at fertilization. This is particularly true of human fertilization, where the availability of eggs for research purposes is severely restricted. As a consequence of this, most of the significant advances in our understanding of mammalian fertilization have resulted from studies on animals, particularly the mouse. This review summarizes our current knowledge of the molecular aspects of mammalian fertilization from the point of view of the fertilizing spermatozoon. Particular reference is made to those advances in our knowledge of human fertilization mechanisms. Further understanding of the molecular basis of human fertilization is of paramount importance for the development of new methods of contraception and also for the rational diagnosis and treatment of certain forms of infertility.