THE STRENGTH OF THE GENETIC EFFECT - IS THERE ROOM FOR AN ENVIRONMENTAL INFLUENCE IN THE ETIOLOGY OF SCHIZOPHRENIA

The evidence for a genetic contribution to schizophrenia is compelling. However, the pattern of inheritance is complex and it is usually assumed that environmental factors also have a role that will eventually be identified. We argue that this is not necessarily the case. While a hypothesis combining genetic diathesis with environmental stress cannot be disproved, it is also possible that 'non-genetic' factors consist entirely of stochastic events affecting gene expression or structure.