Schizophrenia as a Complex Trait

Abstract

Despite evidence of heterogeneity across studies, these meta-analytic results from 12 published twin studies of schizophrenia are consistent with a view of schizophrenia as a complex trait that results from genetic and environmental etiological influences. These results are broadly informative in that they provide no information about the specific identity of these etiological influences, but they do provide a component of a unifying empirical basis supporting the rationality of searches for underlying genetic and common environmental etiological factors.

Psychosocial working conditions, occupational groups, and risk of disability pension due to mental diagnoses: a cohort study of 43 000 Swedish twins

“…Moreover, both mental disorders (34)(35)(36) and DP due to mental diagnoses (37,38) have been shown to be moderately heritable in earlier studies. However, whether choice of occupation and, hence, type of working conditions are heritable or not has so far not been studied.…”

Family-Based Whole-Exome Sequencing for Identifying Novel Variants in Consanguineous Families with Schizophrenia

“…The lifetime prevalence of SCZ is approximately 4.0 per 1,000 worldwide (6). Classical twin, family, and adoption studies indicate a heritability of up to 80% for SCZ, reflecting a strong genetic influence (7,8).…”

Genesis of a complex disease

“…This is hardly surprising given that Swiss psychiatrist Ernst Rüdin -an early proponent of the argument that the condition is a single-gene disorder -advocated the view that people with mental illnesses should not have children 3 , and justified the sterilization and murder of people with schizophrenia. Despite the disease's long and contentious history, by the end of the twentieth century there was consensus that genetic factors were involved 4 . But agreeing that genetics has a part to play is not the same as finding individual genetic regions (loci) that contribute to disease susceptibility.…”