Limitation of the diathesis-stress model in explaining schizophrenia - Multiple genes increase vulnerability, each with a small effect on its own - there is no schizogene. Stress comes in many forms, including dysfunctional parenting.
Researchers now believe stress can also include biological factors. For example, Houston et al. (2008) found childhood sexual trauma was a diathesis and cannabis use a trigger.
This means that there are multiple factors, biological and psychological, affecting both diathesis and stress.