Achilles, Helen of Troy, and Aphrodite were all said to have had red hair. All these millenia later, their names are still known us , but probably not for the reason that they never died. In Greek mythology, you see, it was believed that red-haired people turn into vampires after they died.
Walk into the tall weeds with us as we navigate through the genetics of red hair in dogs. Your captains on this trip (us) are not geneticists, so input is welcome from readers who are.
There are only two basic pigments that determine the color of canines, eumelanin (black) and phaeomelanin (red), and all the different color variations are created by these two pigments, both forms of melanin. There are at least three, and possibly as many as four gene series that determine where, on the dog and along the length of the hair that eumelanin and phaeomelanin appear. These pigments are produced within specialized cells called “melanocytes” located in the canine epidermis and hair follicles, and their production is controlled by the melanocortin 1 receptor (MC1R) gene, also known as “extension.”
Phaeomelanin (the red pigment) has a “default” color of gold or yellow. It creates reds that can range from the deep red of the Irish Setter (an example of a breed that is “fixed” for red) to dogs that are gold, orange, cream, yellow or tan. What makes the color vivid or more muted is the intensity of phaeomelanin that is controlled by genes. Put another way, it’s what determines whether an Irish Setter’s coat is red, mahogany or a rich chestnut. This pigment is produced only in the coat and impacts only hair color. Eye and nose color are affected by Eumelanin. As an aside, if you have freckles, you can blame your phaeomelanin.
Some superstitious people say that rubbing the head of a redhead will bring you good luck, and we can’t disagree. How lucky are the people who get to live with a breed like the Irish Setter below???