Psychiatric genetics

Psychiatric genetics, a subfield of behavioral neurogenetics, studies the role of genetics in psychological conditions such as alcoholism, schizophrenia, bipolar disorder, and autism. The basic principle behind psychiatric genetics is that genetic polymorphisms, as indicated by linkage to e.g. a single nucleotide polymorphism (SNP), are part of the etiology of psychiatric disorders.

The goal of psychiatric genetics is to better understand the etiology of psychiatric disorders, to use that knowledge to improve treatment methods, and possibly also to develop personalized treatments based on genetic profiles. In other words, the goal is to transform parts of psychiatry into a neuroscience-based discipline.

Linkage, association, and microarray studies generate raw material for findings in psychiatric genetics. Copy number variants have also been associated with psychiatric conditions.

Most psychiatric disorders are highly heritable; the estimated heritability for bipolar disorder, schizophrenia, and autism (80% or higher) is much higher than that of diseases like breast cancer and Parkinson disease. However, linkage analysis and genome-wide association studies have found few reproducible risk factors.

Several genetic risk factors have been found with the endophenotypes of psychiatric disorders, rather than with the diagnoses themselves. That is, the risk factors are associated with particular symptoms, not with the overall diagnosis.