As in meta-analyses of other complex traits which identified large numbers of common risk variants, 27,28 the test statistic distribution from our GWAS deviates from the null (Extended Data Figure 2). This is consistent with the previously documented polygenic contribution to schizophrenia. 10,11 The deviation in the test statistics from the null (λGC = 1.47, λ1000 = 1.01) is only slightly less than expected (λGC = 1.56) under a polygenic model given fully informative genotypes, the current sample size, and the lifetime risk and heritability of schizophrenia.29
