A KEY TO MALE INFERTILITY

SCIENTISTS have discovered why some men are infertile and it could save women from intrusive fertility procedures.

The “keys” in some sperm do not fit their partner’s “locks”, according to a study in the journal Genome Research.

It was thought that the sperm simply delivered the father’s half of the DNA for an embryo to develop but British researchers have found some genes in the sperm are left exposed, allowing them to play an important role.

The molecule of a protein called CTCF is at the heart of the mechanism. Dr David Iles, at the University of Leeds, said: “CTCF sets the stage during sperm development and open ‘bases’ can be recognised by CTCF in eggs.” About 330,000 British men are infertile for no known reason.

Co-author Dr David Miller said: “Our research offers a plausible explanation.” The discovery could lead to a test for men.

That would spare up to a quarter of women undergoing fertility checks and sharply decrease the 75 per cent failure rate of in-vitro fertilisation by filtering out men with no chance of success.