Teeth and teaching

Razib Khan has a short but worthwhile post about dental health and heritability: “The moral measure of bad teeth”.

As someone who is quite conscious of the power of genetics, I was quite taken aback by this blind spot. I realized that not only did I attribute my own rather fortunate dental health (so far) to my personal behaviors, but, I had long suspected those with dental issues of less than optimal habits. Obviously environment (e.g., high sugar diet) does matter. But apparently a great deal of the variation in the trait is heritable.

Tooth pathologies are a great example of heritability, because they provide a discrete character (cavities or no cavities) with an age-dependent component, a meristic (how many cavities) component, and several well-characterized environmental components. They’re wonderfully multifactorial – unlike, say, obesity, which is usually understood only along a single factor dimension. Plus, teaching students about this stuff actually helps them address their own health needs, as well as those of their future children.