When a specific gene needed for energy production in hair color cells is turned off in mice, the cells that give hair its color die off, causing the fur to turn gray over time.

When a certain gene is turned off in hair color cells in mice, their fur starts to gray early because the cells die off — but the ones that survive can still make pigment just fine.

When a certain gene is turned off in pigment cells in mice, their fur starts turning gray around 4 months old, and by 8 months, most of their hair has lost color — but normal mice don’t go gray, so this gene might help keep hair colored.

When the energy factories inside hair follicles don't work right, they make too many harmful molecules that damage the color-producing cells, making hair turn gray faster.

In mice with a specific genetic problem, hair turns gray because the stem cells that make hair color die off first—not because the color-making process itself is broken.

When a certain gene is turned off in mice, it damages the stem cells that give hair its color—but not the regular color-making cells—so the hair gradually loses pigment and turns gray or white.