Decoded: Why you turn bald or have grey hair

The presence or absence of a group of cells may be behind your balding, or greying hair, as well as the cause for those lush tresses, researchers say.

The findings showed that a protein called KROX20 -- commonly associated with nerve development -- turns on in skin cells that become the hair shaft. 

These hair precursor, or progenitor, cells then produce a protein called stem cell factor (SCF) -- essential for hair pigmentation.

In the study, when researchers from the University of Texas Southwestern Medical Center, deleted the SCF gene in the hair progenitor cells in mouse models, the animal's hair turned white. 

When they deleted the KROX20-producing cells, no hair grew and the mice became bald.

The results, published in the journal Genes and Development, could one day help identify possible treatments for balding and hair greying.

If cells with functioning KROX20 and SCF are present, they move up from the base, or bulb, of hair follicles, interact with pigment-producing melanocyte cells, and grow into pigmented hairs.

But without SCF, the hair in mouse models was grey, and then turned white with age. Without KROX20-producing cells, no hair grew, the study said.

"With this knowledge, we hope to create a topical compound or to safely deliver the necessary gene to hair follicles to correct these cosmetic problems," said Lu Le, Associate Professor at the university.