Male Birth Control Treatment Could Focus on Sperm Proteins, Not Hormones

A male form of "the pill" has stymied researchers for years, but now a new study finds that such male birth control may be possible by blocking a single protein in sperm cells. In a mouse study, the researchers focused on a protein called calcineurin, which is found in the sperm-producing cells of the testes as well as other cells in the body. The researchers genetically engineered mice so that they lacked a gene that makes part of the calcineurin protein but is activatedonly in sperm-producing