“Heritability refers to the variance within a population, and doesn’t refer to risk of genetic transmission to a specific individual. Put simply, saying schizophrenia is 80% heritable means that genes account for 80% of the causation of schizophrenia in the population. That doesn’t mean that having a parent with schizophrenia means you have an 80% chance of getting the disorder.”
– Samuel H. Barondes, M.D.
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