Genetic correlates of socio-economic status influence the pattern of shared heritability across mental health traits

• Published in: Nature human behaviour 2021-08, Vol.5 (8), p.1065-1073
• Main Authors: Marees, Andries T., Smit, Dirk J. A., Abdellaoui, Abdel, Nivard, Michel G., van den Brink, Wim, Denys, Damiaan, Galama, Titus J., Verweij, Karin J. H., Derks, Eske M.
• Format: Article
• Language: English
• Subjects: 45; 631/208; 631/477; 692/699/476; Alcohol Drinking - genetics; Anorexia Nervosa - genetics; Anxiety Disorders - genetics; Attention Deficit Disorder with Hyperactivity - genetics; Autism Spectrum Disorder - genetics; Averages; Behavioral Sciences; Biomedical and Life Sciences; Bipolar Disorder - genetics; Change agents; Comorbidity; Depressive Disorder, Major - genetics; Educational Status; Experimental Psychology; Genetic diversity; Genetic Predisposition to Disease; Genetic Variation; Genome-Wide Association Study; Genomics; Health problems; Heritability; Humans; Income; Latent Class Analysis; Life Sciences; Medical diagnosis; Mental disorders; Mental Disorders - genetics; Mental Health; Microeconomics; Models, Genetic; Neurosciences; Obsessive-Compulsive Disorder - genetics; Personality and Social Psychology; Polymorphism, Single Nucleotide; Schizophrenia - genetics; Smoking - genetics; Smoking Cessation; Social Class; Socioeconomic factors; Socioeconomic status; Substance-Related Disorders - genetics; Tourette Syndrome - genetics
• ISSN: 2397-3374; 2397-3374
• DOI: 10.1038/s41562-021-01053-4

Epidemiological studies show high comorbidity between different mental health problems, indicating that individuals with a diagnosis of one disorder are more likely to develop other mental health problems. Genetic studies reveal substantial sharing of genetic factors across mental health traits. However, mental health is also genetically correlated with socio-economic status (SES), and it is therefore important to investigate and disentangle the genetic relationship between mental health and SES. We used summary statistics from large genome-wide association studies (average N  ~ 160,000) to estimate the genetic overlap across nine psychiatric disorders and seven substance use traits and explored the genetic influence of three different indicators of SES. Using genomic structural equation modelling, we show significant changes in patterns of genetic correlations after partialling out SES-associated genetic variation. Our approach allows the separation of disease-specific genetic variation and genetic variation shared with SES, thereby improving our understanding of the genetic architecture of mental health. Marees et al. show changes in patterns of heritability and genetic overlap between mental health problems after removing genetic variation associated with socio-economic status.