Scientists studying mice have identified a gene which could boost human fertility.
Experts say the discovery, announced in a journal today, could help people struggling to conceive naturally.
A Durham University team working with scientists from Osaka University in Japan were studying fertility in mice when they discovered that the gene, which makes a protein called PDILT, enables sperm to bind to an egg, a process essential to fertilisation.
They found that when the gene was switched off in male mice, less than three per cent of females' eggs were fertilised compared to more than 80% in mice when the gene was left switched on. It is the first time that a gene of this type has been linked to fertility.