For over six decades contraception has been focusing mainly on women. Of course there are methods of contraception for men also, but the pill used for birth control has been exclusively for women.

However science has news for men; researchers could develop a pill for men. This pill is not going to be of hormonal nature, it will contain a specific protein blocker.

PPP3CC/PPP3R2 also known as calcineurin is the targeted protein, which is located in the sperm tail. The role of this protein is to enable the sperm to penetrate the outer membrane of the egg. Thus, blocking this protein will make it impossible for the sperm to fertilize the egg.

Researchers in Japan identified a version of calcineurin that is only found in sperm. They experimented on mice and made them infertile. The scientists underwent through many experiments, including genetic modifying.

They wanted to be sure that they have to do with the specific protein so they identified the gene responsible for synthesizing that protein. First they genetically modified the mice and they concluded that the protein was responsible for the movement of spermatozoids.

Further they experimented on normal mice to see if they can block calcineurin, and the experiment was successful. By using the drugs cyclosporine A and FK506 (both blockers of calcineurin) the mice became infertile. This was reversible after the drugs were stopped.

The researchers at Osaka University, Japan, also identified this specific protein in human sperm. Their aim is to develop a male contraceptive that acts rapidly and is reversible in humans also.

Patricia Morris, biomedical researcher, when reading about this research stated that "The holy grail of any drug development is, you want it to be specific, and that's what makes [this] such an enticing, kind of exciting prospect."


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