• Question: Why are some people's eyebrows a different colour to their hair colour (e.g. brown eyebrows and blond hair)?

    Asked by Kit Kat to yoyehudi, Oli, Nina, Kerrianne, Ed on 8 Nov 2017.
    • Photo: Yo Yehudi

      Yo Yehudi answered on 8 Nov 2017:

      Oooh, interesting question! I have no idea but I’d love to se if the others come up with a good answer apart from “maybe they dye their hair” 😉

    • Photo: Oli Wilson

      Oli Wilson answered on 8 Nov 2017:

      I think it’s all to do with which cells turn on which genes. Your genes control the production of chemicals called melanins which give hair their colour (there’s brown and black eumelanin, and pheomelanin which is red), and which are produced by cells called melanocytes. Although all your cells carry the same DNA, it isn’t all active in all the places – cells only switch on the genes they need to do their job, so things like hair or teeth are only built in the right place (unless you have a weird kind of cancer called a teratoma). Melanocytes in different parts of your face might switch on different genes, so produce different amounts of the melanins, resulting in different colour hair in different places. It’s the same reason why some men with dark hair will have bits of ginger in their beards 🙂

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