If you have ever found yourself stroking your beard and wondering ‘why all the red patches?’ then you have your chromosome 4 to thank.
Males aged 18 to 60 have been hit by an epidemic of beard growing over the past two years or so. Experts have underestimated how long it will continue to rage, although if current trends continue, all young urban media professionals will be affected by 2017 (probably).
As more guys jump onto the hairy bandwagon, you’ve probably asked yourself, why are so many beards ginger even if their hair is dark? Even if they don’t have a redhead in the family?
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.
She told him it’s all down to the MC1R-gene. The gene coding for hair colour is called “incomplete dominant hereditary traits,” meaning hair color isn’t as simple as one gene coding for one color of hair. The genes can be expressed differently in different areas of your body, like your head, beard, eyebrows or pubes.
Haak-Bloem explained that it’s all to do with the genes that code for the amount of different pigments, called melanin, in your hair. She explained that hair color is dependent on two of these pigments: eumelanin, the black pigment, and pheomelanin, a red pigment.
She added: “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.”
Haak-Bloem also said that if you only inherited one of these mutated genes, red hair can appear in sporadic places because of the variety of ways the gene can be expressed.
So, there you have it. That odd ginger beard in your family isn’t just the product of extramarital activity with a crimson-locked lothario.
Beard hair is quite different to head hair; it is coarser, curlier and doesn’t fall out as we get older. Comparatively little work has been done on the genetics of human hair colour, but it is believed that in order to have a ginger beard you must be a carrier for the recessive gene on chromosome 4. With two copies of this gene you will have ginger hair all over, but with just one, the hair on your head will be brown or auburn and your beard will be ginger.
Why is Facial hair thicker then head hair
The hair on your face, along with most of your body hair, is androgenic hair. Essentially when you go through puberty the hormones your body begins to produce can bind to cellular receptors triggering a series of biochemical steps that ultimately activate a specific set of genes. Some of these genes are very similar or identical to the ones that produce head hair like the genes for ubiquitous proteins like collagen. Others are specific for the hair on your face. For example, some regulate the growth patterns which explains why facial hair typically can’t grow as long. Others control how thick each individual hair fiber becomes, and the specific protein composition which influence strength and thickness. These hormonally derived differences in gene activation are ultimately what dictate the differences you see and feel in the different hair types.