Those sneaky gingers pop up everywhere


I have a brother with red hair. I also have a son with red hair. Once upon a time, my beard and mustache contained many red hairs among the dominant browns. If you’ve ever wondered how these gingers appear all over the place, Petra Haak-Bloem offers a good explanation (although it needs some editing: how many different ways can they spell pheomelanin?).

The shade of hair color is determined by the amount of melanin, or pigment, in the hair. Your DNA not only encodes what kind of pigment you have, but also how much of it. “For white people the shades are dependent on two sorts of melanin: eumelanine (black pigment) and pheomelanine (red pigment). Hair cells of dark haired people only contain eumelanine. Blondes have less eumelanine. And redheads’ hair contains mostly pheomelanine,” Haak-Bloem says.

“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 proteine plays an important part in converting pheolmelanine into eumelanine,” Haak-Bloem tells me. “When someone inherits two mutated versions of the MC1R-gene (one from each parent), less pheomelanine is converted into eumelanine. The feomelanine accumulates in the pigment cells and the person ends up with red hair and fair skin.”

The unexpectedly red beard is the effect of the same mutation in the MC1R gene. When you only have one mutated MC1R, red hair can appear in (unwanted) places. But even Haak-Bloem wasn’t completely sure of the mechanism. Having a deviant red beard has never been linked to any deadly diseases, so it’s pretty low on the research priorities list.

That’s basically it, although it is sad that she has to admit that research on this stuff has a low priority. It shouldn’t! Maybe the specific question of why people have red hair isn’t a big deal, but it touches on concepts that basic biology education often neglects.

One thing has to be made clear in a world where everyone expects the answer to be something like inheritance of a gene for red hair. There is no single gene for eumelanin or pheomelanin! The pigments are the product of a biochemical pathway, and there are multiple enzymes that manage each step. Both pigments are synthesized from the amino acid tyrosine via divergent pathways.

The other important idea here is that gene expression is regulated, not just at the genetic level, but cytoplasmically. All your cells have the enzymes for making pheomelanin and eumelanin and are genetically identical, but the balance shifts in different tissues, so people with brown hair (lots of eumelanin) will express lots of pheomelanin (reddish!) in the skin of their lips and nipples.

Hair pigmentation is actually a cool subject to study. We know it’s evolutionarily significant in many species (for example, Hoekstra’s work on coat color variation), and it’s also a visible marker for variations in gene regulation. What is the basis for male pattern baldness? Why is my beard going gray so much more quickly than my head hair? Specifically, these aren’t particularly pressing concerns, but they are indicative of a lot of invisible patterning going on in our skins, made manifest by aging or illness…and it makes me curious to understand these subtle variations.


  1. Nerd of Redhead, Dances OM Trolls says

    Ah, chemistry and gingers….
    Pheomelanin is some benzothiazine polymers.

  2. shaneevans says

    Excellent example of a biochemical pathway. I’m going to use it this semester. I am wondering about trichosiderin. I thought that was the hair color pigment for redheads.

  3. blf says

    My sister had red hair. We stole a joke from, ahem, Readers Digest, to explain it: “She washed her hair, didn’t dry it, so it rusted.”

  4. Al Dente says

    Why is my beard going gray so much more quickly than my head hair? Specifically, these aren’t particularly pressing concerns, but they are indicative of a lot of invisible patterning going on in our skins, made manifest by aging or illness…

    When I was much younger, my hair was completely black. It started turning gray when I was in my early 20s. By the time I was forty my hair was almost completely white, except for my beard, which is still salt and pepper. I demand an explanation of why my genes are laying down on the job!

  5. citizenjoe says

    Huh. Back in the 60s, my beard was red, though my head-hair was brown; I shaved to go “Clean for Gene” and shaved for the next 35 years (in the Army); then I retired, and my beard came in brown and grey, with no trace of red.

  6. shouldbeworking says

    I’m using me of this in my general science course this coming semester. It’s at a level this graying (formerly reddish) haired physics teacher can understand.

  7. kimbeaux says

    While I cannot give you an explanation as to why your genes are laying down on the job, perhaps I can distract you with this.

  8. says

    A question for those who are or know redheads, or are just more observant than me, are freckle patterns permanent? I know the individual freckles grow or shrink with varying exposure to the sun, but do they stay in the same pattern, or shift around? If I’m doing a portrait of someone with freckles, how important is it that I get the freckles exactly right? Or, to put it another way, how random can I do them and get away with it?

  9. madtom1999 says

    It does look a fascinating subject. I was always intrigued by the colour changes in animal coats when domestication takes place. There was a Russian that bred from tame minks and they became multicoloured.

  10. madtom1999 says

    @8 Nelc. Probably very important to get the freckles right – I dont think they change pattern and people are remarkably good at remembering even random seeming patterns and missing just one of several hundred can be quite noticeable to someone familiar with the face.

  11. redwood says

    My father had black hair, blue eyes and a red beard. I was called carrot-top as a kid, but as I’ve gotten older my hair has darkened until recently when the gray in it has lightened it a bit. I burn rather than tan and have lots of freckles on my arms and legs, not so many on my face but they don’t change position.

    My sister was fair as well and she died of skin cancer (melanoma). My dermatologist took one look at me when I told him that and said I had to be really careful about sunlight and moles, so I think there might be some danger to being red-headed after all. Surely there’s been research along those lines.

  12. carlie says

    A youngster I know has almost completely red sideburns, and we’re talking orangey-red, not auburn or strawberry blond, but completely blond hair.

  13. Saganite, a haunter of demons says

    How come any gingers have freckles at all then, if souls aren’t real, as you claim, huh? Checkmate, atheists!

  14. jonmelbourne says

    I used to have a quite prominent ginger streak in my beard (and nowhere else) and so far the ginger hairs are the only ones that have noticeable gone gray. Damn those gingers, damn them to hell.

  15. microraptor says

    How come any gingers have freckles at all then, if souls aren’t real, as you claim, huh? Checkmate, atheists!

    Because it’s a typo. I earn a freckle every time I steal a sole!

  16. says

    Jonmelbourne I have the same problem: Mom was born in Norway, and Dad’s family was Scotch-English, so I’ve got pretty consistent DNA. I was tow-headed as a child and slowly darkened to dull brown. But I had red streaks at my temples, which rescued me from insipidity. Of course, the red in my hair when white by the time I was 32 — which I rather liked. It’s now all salt-and-pepper, which is even worse than dull brown.

    However, there are worse things than boring hair.

  17. naturalcynic says

    Interesting how hair changes as we age. I started out red, turned strawberry blonde on top during my lifeguarding days around 20, but remained red underneath, then turned all strawberry blonde all over in my 30’s and now [60’s] I am greyish blonde. Started out with a very red beard, but that totally greyed by about 50; axillary hair went from red to blonde to grey about the same time my head hair changed; and the pubic hair is still strawberry blonde after starting out bright red. My daughter is still a true ginger at 29 but both my father and one of my brothers went from red to mousy brown by the time they were 20.
    BTW, what changes to significantly darken many child blondes?

  18. Pen says

    Another cool hair thing is premature white hair which runs in my family, with a significant white streak by the early teen years and near complete whiteness by 30. Apparently, it’s a known enough thing in Europe and Asia to have its own legends. What is with that, genetically?

  19. says

    Ok, so the YOBling is a full on RED! head. I was ultra-blonde as a child, but when I got old enough for one, my beard came in fire engine red. Heck, back in the day, my biker handle was “Red Breard”. Now, I’m bald and grey bearded.

    If Tim Minchin is right that only a ginger can call a ginger, “Ginger”, can I call the YOBling “Ginger”?

  20. chrislawson says

    Actually there is a deadly disease associated with red hair: melanoma, and it’s not all that uncommon in my part of the world. Not that this is likely to drive research because nobody really believes genetic studies are going to play much of a role in reducing melanoma rates.

  21. Trebuchet says

    Forty years ago, I had blonde hair and a red beard. Now I have neither hair nor beard. I can’t do anything about the hair, and the beard, if I grew it, would be gray.

  22. nutella says

    It’s not the red hair that’s associated with melanoma — it’s the pale skin which almost always goes with red hair but is also common with other hair colors. Mayo Clinic lists the risk factors as:

    Fair skin. …
    A history of sunburn. …
    Excessive ultraviolet (UV) light exposure. …
    Living closer to the equator or at a higher elevation. …
    Having many moles or unusual moles. …
    A family history of melanoma. …
    Weakened immune system.

    But darker-skinned people are not risk-free. Bob Marley, for example, had acral melanoma.

  23. Pierce R. Butler says

    When younger, I had red hair everywhere.

    Now I have darkish brown hair on my head and chest, a mostly-white beard with some remaining red, and red pubic hair with white traces. Arm and leg hair remains red.

    Both my father and his father went bald in middle age; I’ve apparently inherited the full hair retention of men on my mother’s side.

  24. marcus says

    jrochest @18 I had a woman-friend whose hair came out a deep red, and was always red at the roots. Sunlight, however, turned it a brilliant white, it was very becoming on her (also it never grew past a certain length). Her dad’s hair was the same, he was of Norwegian descent. Mom was Irish. Interesting effect of these melanins.

  25. warney says

    The first line of this blog led me to believe that we were about to be granted a major scoop:

    “I have a brother with red hair. I also have a son with red hair.”

  26. blf says

    dannysichel, madtom1999, Don’t forget Dr Belyaev’s complementary experiment with rats, breeding for aggression and not tameness. My understanding is the rats are now so aggressive it is forbidden for anyone to be alone in the room with them, and you must wear chain-mail gloves when handling them.

  27. chigau (違う) says

    My understanding is the rats are now so aggressive it is forbidden for anyone to be alone in the room with them, and you must wear chain-mail gloves when handling them.

    What colour fur do these rats have?

  28. frog says

    I come from an Irish (American, but all the immigration happened in the 20th C) family, and we have some seriously scrambled genetics when it comes to the hair color. Everything from pale blond to black, with redheads in various shades, though tending toward auburn more than true carrot-ginger. We also have textures from pin-straight to Greg-Brady-perm-curly, though most of us have wavy hair.

    But we all have freckles. NelC, my freckles do wax and wane with the season, but the most prominent ones (which are many) are distinctive and I know where they are. (In my family, “is it a mole or is it a freckle?” is a bit of philosophical debate.) I notice when new ones pop up and I notice when some go away or change; this is useful at the dermatologist’s office every year.

    I think for the larger mass of freckles you could get away with an impressionistic rendering, but any darker, more distinct ones are part of the person’s face and would be noticed by friends and family if they disappeared.

  29. shadow says

    @19 NelC:

    Like going bald.

    my father once said that Nature made only a few perfect heads — the rest were covered with hair. (He was bald)