DNA is pretty remarkable stuff, the way it can control the development of so many different parts of our body. But one of the ways that it accomplishes this is by using some of the same genetic codes to control many different structures.
Things like hair, teeth, and fingernails may all seem very different to us, but they’re actually very similar in some ways, as they all derive from scales on fish. In fact, tooth enamel wasn’t developed first in teeth–it first appeared on the faces of some primitive fish. One of the disadvantages of this approach is that a disadvantageous variation in a particular gene can lead to defects in multiple tissues. For example, some gene variations can cause hair problems as well as make your teeth vulnerable to cavities.
How Your Hair Signals Your Cavity Risk
Researchers realized that hair and teeth depend on the same protein, keratin. In hair, it’s a major structural component, but in tooth enamel it’s one of the non-mineral components of tooth enamel. They also found that certain variations affected the development of hair and also tooth enamel.
One gene that controls keratin in hair and tooth enamel is KRT75. Some variations of KRT75 that have been identified can contribute to ingrown hairs, hair that doesn’t grow vigorously and falls out easily, or hair that is fragile and looks like a string of tiny beads.
They also found out that the variation causing poor hair growth, called loose anagen hair syndrome, was also associated with increased risk of cavities in children, when loose anagen hair syndrome is most active.
They also found that the variation of KRT75 that increases risks for ingrown hairs causes structural weaknesses in teeth, such as tiny cracks, enamel defects, and places that allow bacteria to get inside the tooth enamel.
With these genetic variations, it seems, some people are much more likely to develop cavities than others.
Biology Is Not Destiny
But you don’t have to be bound by your genetic heritage. If you know you may be vulnerable to tooth decay, improved oral hygiene, including regular professional cleanings, can help. And if you do experience tooth decay, advanced dental materials can be used to repair your teeth. Porcelain crowns aren’t affected by your genes!