Science Explains: Why Do Non-Ginger Guys Have Ginger Beards

You probably know at least one man with a red beard and dark hair. Given the trend of growing the beard, it is surprising how many men actually have hair color different from the color of the beard. 

Dark hair men with a ginger beard

In order to understand the way in which genes define hair color, we must know that genes really define hair color. From the standpoint of genetics, hair color is very complex. “The genes that determine hair color are so-called ‘incomplete dominant hereditary traits.’ This means that there isn’t one single gene that’s dominant over the rest, but all genes influence each other,” says Petra Haak-Bloem, the Dutch specialist of the National Center for Genetics and hereditary traits. 

The same gene may be otherwise present in everyone. This allows a multitude of possibilities, one of which is that the hair color is different from the color of pubic hair, beard and axillary hair.

"Generally speaking, people inherit the color not only from their parents but also from their grandparents and earlier ancestors," says Haak-Bloem. 

What is the cause of a red beard?

The shade of hair color is determined by the amount of melanin or pigment in the hair. Our DNA is not only decoding what pigment we have, but also how much pigment we have.

'For Caucasian hue depends on two types of melanin: eumelanin (black pigment) and pheomelanin (red pigment). "The cells of humans with dark hair contain only eumelanin. Blonde people have less eumelanin, and redheads have mostly pheomelanin ," says Haak-Bloem.  

More than a decade ago, scientists have discovered that a single gene (MC1R) on chromosome 16 plays an important role in giving people with red hair. The task of the MC1R protein is production of melanocortin 1. That protein plays an important role in the conversion of pheomelanin in eumelanin, says Haak Bloem.

'When someone inherits two mutated versions of the gene MC1R (one from each parent) less pheomelanin is converted into eumelanin. Pheomelanin accumulates in the cells of the pigment and the person thus gets red hair and fair skin.

Unexpectedly red beard effect is the same mutation in the MC1R gene. When you only have one mutated MC1R, red hair can occur at various places on the body. But the mechanism is not yet known.