If there's a glitch in a gene called Mitf, it might cause the cells that give hair its color to go haywire too early, making animals gray faster as they age.

As we age, pigment cells in our hair can go haywire and stop working properly — this might be sped up if there's a glitch in a key gene called MITF that controls how these color cells develop.

As we age, the stem cells that give color to our hair can start acting up — they might turn into pigment cells too soon or in the wrong place, which could be why our hair turns gray.

As we get older, the stem cells that keep our hair colored might stop working properly because of problems in their internal repair system, and once they're gone, our hair turns gray for good.

When the stem cells that give your hair its color get worn out or change too early because of stress in the cells, they stop making pigment, and your hair turns gray permanently.

Going gray might happen because the stem cells that keep your hair colored stop working properly as you age, according to studies in people and specially tagged mice.