It isn't news that your hair texture is just one part of what makes us totally unique individuals. Plenty of physical attributes are predetermined by genetics. From eye color, to height and bone structure, we all possess visible ties to our family ancestry through genetics. Today we’ll explore why our hair looks the way it does and exactly how the genes you inherit from your parents, and sometimes even your parent’s parents, can determine your hair texture!
The Basics
As you may know, each piece of hair on your head has two basic components. There’s the shaft which is the black part that lies above the scalp and there’s the hair follicle that is inside of the skin not visible to the eye.
The hair follicle is actually considered a bodily organ, and it produces your hair. These follicles are essentially the holes on your scalp that your hair grows out of, nourishing each strand by providing it with blood and nutrients. The shape of these holes are the key to determining your hair texture and how your hair strands will look as it grows. Now how do genes tie into this? Well- the shape of these follicles are affected by the genes that you inherit from your parents!
The above figure shows how the shape of the follicle affects the shape of the hair strand. The nature of hair follicles directly impact the texture of your individual hair strands. If the follicles are symmetrical, hair grows to be straight, whereas if the follicles are asymmetrical, they produce oval and circularly shaped hair that tends to curl as it grows.
Learn more about the anatomy of hair in our blog post about the subject here!
What’s In Your Genes?
Having curly hair is considered an “autosomal dominant trait”. You may already know that some traits can be either dominant or recessive, and remember doing countless punnet squares in middle school, but autosomal dominant traits are a bit more complex.
Autosomal dominant traits are passed down from a single parent that has a mutated dominant gene. This means that their offspring will have a 50% chance of having a child with that same mutated and dominant gene. With that said, if the parents have different hair types, for example if one has straight hair, while the other has curly hair, offspring would get genes of both types, but the dominant curly hair gene would always overtake the straight hair gene and express itself in the offspring giving them their lovely waves, kinks, and/or curls!
In some cases, when there are differences in the strength and type of genes, kids can end up having hair that is somewhere in the middle – a little straight and a little curly. The same happens with parents who both have curly hair, with offspring having varied levels of texture inherited. Just as with skin tone and eye color, entire families can possess an extensive range of textures throughout!
So, no matter what type of hair you have, you definitely have your parents to thank! Although we can always attempt to manipulate our hair texture with braids, twist outs, and even chemical straightening or heat tools, at the end of the day, our texture was already predetermined. Always be sure to love your hair, and take good care of it. It’s an incredible part of what makes you, you!