Let’s take another look at heritability and genetic causation. I go on ranting on this topic as we so often hear that this or that is “highly heritable” or “mostly caused by genes”. For complex conditions, these claims are made based on estimates of heritability (see last week’s post).
Take-home message: genes matter, but genetic causation is much less clear-cut than assumed in statements such as “autism is 80% genetic”. The enigma of the “missing heritability” is not so enigmatic after all, but results from a simplified translation of heritability estimates to causal pathways.