To examine shared genetic etiology among different psychiatric disorders Lee et al. used genome-wide genotype data (from the Psychiatric Genomics Consortium) for cases and controls in schizophrenia, bipolar disorder, major depressive disorder, autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (ADHD).
After univariate and bivariate analysis, the genetic variation within and covariation between disorders was estimated. SNPs explained 17-29% of the variance in liability.
The genetic correlation calculated using common SNPs was:
- high between schizophrenia and bipolar disorder (0.68 ± 0.04 s.e.),
- moderate between schizophrenia and major depressive disorder (0.43 ± 0.06 s.e.),
- moderate between bipolar disorder and major depressive disorder (0.47 ± 0.06 s.e.),
- moderate between ADHD and major depressive disorder (0.32 ± 0.07 s.e.),
- low between schizophrenia and ASD (0.16 ± 0.06 s.e.)
- and non-significant for other pairs of disorders as well as between psychiatric disorders and the negative control of Crohn’s disease.
The authors of this study conclude that shared genetic etiology for psychiatric disorders can encourage the investigation of common pathophysiologies for related disorders.
Cross-Disorder Group of the Psychiatric Genomics Consortium, Lee SH et al. Nat Genet. 2013 Aug 28;45(9):984-94. PMID: 23933821
Posted by Yannis Trakadis, MD