When applying bivariate MIXeR to mental disorders, there was a pattern of extensive genetic overlap between the four mental disorders, with almost complete genetic overlap across all disorders (fig. 2, supplementary table 5). Further, AIC differences indicated that MiXeR-modelled overlap was not distinguishable from maximum overlap (supplementary results). This pattern was most evident for schizophrenia and BIP which were almost completely overlapping, with 8.5K (sd=0.3K) shared variants, 0.1K (sd=0.2K) unique BIP variants and 1.1K (sd=0.4K) unique schizophrenia variants. Since the number of shared variants was almost equal to the total number of ‘causal’ variants, rgs (0.78, SD=0.03) was similar to rg (0.73, sd=0.006), providing further evidence of the highly similar genetic architectures of these two psychotic disorders.
