Human PEM as a target for fertility control

The invention relates to human PEM polypeptide, which plays an essential role in sperm maturation and encoding nucleic acid. The invention includes the use of PEM as a target in male fertility control and for the treatment and diagnosis of male infertility. The invention also includes a selection method for PEM antagonists and the production of binding molecules that specifically recognize PEM. Furthermore, genes that are regulated by the PEM gene part of this invention.