Very little is known for certain about the genetics of schizoaffective disorder. Studies suggest that variations in many genes, each with a small effect, combine to increase the risk of developing the condition. There may also be genetic variations with larger effects in some affected individuals or families, but these variants are rare in the general population, and it is unclear which particular genes are involved.

The genes that have been studied as possible contributors to schizoaffective disorder have diverse functions in the brain. These genes include some that regulate the body's daily (circadian) rhythms, such as the sleep-wake cycle; others that help control the movement (migration) of nerve cells during brain development; and still others involved in sending and receiving chemical signals in the brain. In particular, several genes that have been associated with the risk of schizoaffective disorder provide instructions for making parts of a receptor for gamma-amino butyric acid (GABA), a chemical called a neurotransmitter that sends signals in the brain. GABA's primary role is to prevent the brain from being overloaded with too many signals.

Many of the genetic variations associated with schizoaffective disorder appear also to be involved in schizophrenia or bipolar disorder. Other variations seem to be specific to schizoaffective disorder. However, it is challenging to study the genetics of schizoaffective disorder because the disorder has such significant overlap with these other mental health conditions. In some studies, people with schizoaffective disorder are analyzed in the same group as those with schizophrenia or bipolar disorder, so it can be difficult to determine which genetic variations influence each of these specific diagnoses.


Egosyntonic refers to the behaviors, values, and feelings that are in harmony with or acceptable to the needs and goals of the ego, or consistent with one's ideal self-image.