It’s the stuff of 3rd-grade sex ed: sperm meets egg to make baby. But, surprisingly, scientists have actually been in the dark about one crucial step: how the two sex cells recognize each other amidst the fluid frenzy in the Fallopian tubes. Now researchers have announced that they’ve found the missing piece of this fertilization puzzle, and that the discovery could lead to individualized fertility treatments and hormone-free birth control.
Back in 2005, researchers found the first half of the the puzzle: a binding protein on the surface of sperm they called Izumol (after a Japanese marriage shrine). In the decade since then, scientists have been searching for Izumol’s counterpart on egg cells. Essentially, they’d found the plug but couldn’t locate the outlet.
