Is there a geneticist in the house?
I feel like I have a tenuous grasp on what heritability means and why it is *not* the same thing as saying a trait is genetic.
And yet, reading about this new study on the genetic causes of obesity, I’m confused again. I only have access to the abstract (booooo) but the conclusion, which Marion Nestle talks about in this post, is that the different gene variants associated with increased bmi only account for about 1% of differences in weight.
So how does it work that a trait can have very high heritability, but that same trait have a fairly low correlation with gene variants? Do I just need to take a class? Help.
ETA: This post dealing with the heritability of IQ is a great, though very very long, look at the concept of heritability. Well worth the read if you find these things as interesting as I do.