The incredible popularity of the beard has raised one major question that has until now remained unanswered: why do non-redhead guys have ginger beards?

Perplexed by the question, Adriaan Schiphorst from Motherboard called up Petra Haak-Bloem from Erfocentrum, a Dutch organisation that promotes genetics and awareness of genetic disorders, to get the answers.

According to Erfocentrum, it’s really quite complex:

“The genes that determine hair colour 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,” said Petra Haak-Bloem, a specialist at the centre.

So basically it’s all down to the MC1R-gene. The gene coding for hair colour is called “incomplete dominant hereditary traits,” meaning hair colour isn’t as simple as one gene coding for one colour of hair. The genes can be expressed differently in different areas of your body, like your head, beard, eyebrows or short and curlies.

It all boils down to the genes that code the amount of different pigments, called melanin, in your hair.

Petra goes on to explain:

“More than a decade ago, researchers discovered that one gene (MC1R) on chromosome 16 plays an important part in giving people red hair. MC1R’s task is making a protein called melanocortin 1. That protein plays an important part in converting pheolmelanine into eumelanine.

When someone inherits two mutated versions of the MC1R-gene (one from each parent), less pheomelanine is converted into eumelanine. The (pheomelanine) accumulates in the pigment cells and the person ends up with red hair and fair skin.”

So if your Dad has black facial hair and your Mum is blond it is still possible for you to have a ginger beard… So you don’t have to worry, your mum probably didn’t sleep with the milkman. Probably.