biostudies-literatureTaylor MJWellcome Trust280-289https://www.ebi.ac.uk/biostudies/studies/S-EPMC6439816biostudies-literatureUnknown76(3)<h4>Importance</h4>Psychiatric traits associated with categorically defined psychiatric disorders are heritable and present to varying degrees in the general population. It is commonly assumed that diagnoses represent the extreme end of continuously distributed traits in the population, but this assumption has yet to be robustly tested for many psychiatric phenotypes.<h4>Objective</h4>To assess whether genetic risk factors associated with psychiatric disorders are also associated with continuous variation in milder population traits.<h4>Design, setting, and participants</h4>This study combined a novel twin analytic approach with polygenic risk score (PRS) analyses in a large population-based twin sample. Phenotypic and genetic data were available from the Child and Adolescent Twin Study inJAMA psychiatryAssociation of Genetic Risk Factors for Psychiatric Disorders and Traits of These Disorders in a Swedish Population Twin Sample.PMC6439816106047/Z/14/ZMartin JLu YLichtenstein PLarsson HBrikell ITaylor MJLundstrom SfalseAssociation of Genetic Risk Factors for Psychiatric Disorders and Traits of These Disorders in a Swedish Population Twin Sample.<h4>Importance</h4>Psychiatric traits associated with categorically defined psychiatric disorders are heritable and present to varying degrees in the general population. It is commonly assumed that diagnoses represent the extreme end of continuously distributed traits in the population, but this assumption has yet to be robustly tested for many psychiatric phenotypes.<h4>Objective</h4>To assess whether genetic risk factors associated with psychiatric disorders are also associated with continuous variation in milder population traits.<h4>Design, setting, and participants</h4>This study combined a novel twin analytic approach with polygenic risk score (PRS) analyses in a large population-based twin sample. Phenotypic and genetic data were available from the Child and Adolescent Twin Study in2019-01-01T00:00:00Z2019 Mar2026-05-06T21:33:07.909Z2019-06-06T22:54:25ZS-EPMC64398163056618110.1001/jamapsychiatry.2018.3652