It’s the same for heart disease. And schizophrenia. And drug addiction. And Alzheimer’s. And autism. And diabetes. And bipolar disorder. And intelligence. And pretty much any condition, disease, and behavior we have looked at. Genes do not determine the outcome of almost all human biology and psychology. Dozens or hundreds of genes can be involved, each with small cumulative effects, and all mitigated by the world in which we live.
