RT Journal Article SR Electronic T1 Genetics of educational attainment aid in identifying biological subcategories of schizophrenia JF bioRxiv FD Cold Spring Harbor Laboratory SP 114405 DO 10.1101/114405 A1 Vikas Bansal A1 Marina Mitjans A1 Casper A.P. Burik A1 Richard Karlsson Linnér A1 Aysu Okbay A1 Cornelius A. Rietveld A1 Martin Begemann A1 Stefan Bonn A1 Stephan Ripke A1 Michel G. Nivard A1 Hannelore Ehrenreich A1 Philipp D. Koellinger YR 2017 UL http://biorxiv.org/content/early/2017/03/08/114405.abstract AB Higher educational attainment (EA) is known to have a protective effect regarding the severity of schizophrenia (SZ). However, recent studies have found a small positive genetic correlation between EA and SZ. Here, we investigate possible causes of this counterintuitive finding using genome-wide association results for EA and SZ (n = 443,581) and a replication cohort (1,169 controls and 1,067 cases) with high-quality SZ phenotypes. We find strong genetic overlap between EA and SZ that cannot be explained by chance, linkage disequilibrium, or assortative mating. Instead, our results suggest that the current clinical diagnosis of SZ comprises at least two disease subtypes with non-identical symptoms and genetic architectures: One part resembles bipolar disorder (BIP) and high intelligence, while the other part is a cognitive disorder that is independent of BIP.