A plea for population genetics

The title here is somewhat misleading. This is not just a plea for population genetics, but for quantitative genetics as well. Genetics is a big field. But today it is defined by and large by DNA, the concrete entity in which the abstraction of the gene is embedded. Look at the header of this website, or the background to my Twitter account. Mind you, I’m pathetically informed about molecular genetics, and don’t have a strong interest in the topic! I did consider using the H.W.E. or the breeder’s equation for the header, but in the end I judged it too abstruse and unfamiliar to most readers. DNA dominates when it comes to the modern mental conception of genetics, and we have to live with it to some extent.
But there is also great value in the genetics which has intellectual roots in the pre-DNA Mendelians and biometricians. This genetics exhibits a symbiotic, but not necessary, association with genetics as a branch of biophysics. Yet I come here not to insult or impugn my friends who toil in the trenches of the molecular wars. Rather, I simply want to point out that our world needs balance, and the systematic aerial perspective of population, evolutionary, and quantitative genetics can provide a different kind of intellectual ballast. More importantly, for the mnemonically lazy in the audience pop, evo, and quant gives you information for free. By this, I mean that these are highly theoretical fields, and theory can predict and allow you to infer facts about the world. You don’t need immerse yourself in every scrap of data if you can derive the likely probable pattern from theory.


In some ways you might classify molecular geneticists as hedgehogs and pop and quant geneticists as foxes. Often this is meant to denigrate the group labeled as hedgehogs, with their narrow and single-minded focus on a specific topic or question. But the world needs both hedgehogs and foxes. I would hope that many biomedical geneticists were hedgehogs, with a single-minded devotion to their particular domain of inquiry. On the other hand the world would probably benefit from a sprinkling of foxes within biomedicine as well.

But in some ways pop and quant genetics is more useful in the day to day than molecular genetics. People I encounter regularly talk about heritable traits, and the nature of heritability, without any clear and concise way to frame and flesh out their thoughts. For example, will smart people have smart children? Tall people tall children? Ugly people ugly children? These are questions where the molecular geneticist doesn’t have any tools to tackle, but some quick & dirty quantitative genetic models can help in a pinch. And of course today with the rise of genomics, and the likely ubiquity of personal genomics, some formal frameworks in understanding the system of genetics can be quite handy and practical in the “news you can use” sense.

What next? First, I hope people keep an open mind about things. People seem to have a discomfort with the reality that there are statistical patterns in the world, including heritable ones. Part of this is mathphobia, but part of it is probably Gattacanism. Second, there are good books you can read. Third, feel free to continue reading my blog, but engage in the comments and ask for clarification (the answers are quite likely to come from readers which far greater fluency in these domains than myself). I hope to run into you at a party soon!

Image credit: Wikipedia.

Addendum: Does anyone know of a usable photo of Sewall Wright which isn’t copyrighted?

Source: Discover Magazine – Gene Expression