Men with ginger beards don't necessarily have ginger hair, and it's thanks to chromosome 4.
Asked by: Ricky Gellatly, Oxford
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.
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Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
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