limitations in the Allen Human Brain Atlas that have been noted previously [66], the associations with molecular profiles reported in the current study need to be interpreted with caution. Apart from this, other limitations in the present study should be borne in mind when interpreting the results. For instance, we assumed that discrepancies in analytical approaches of the prior ENIGMA findings (e.g., mega vs. meta-analyses, consistency in how to best adjust for scanner effects) did not have consequential impacts on the reported effect size maps. This limitation can be addressed in future studies that might conduct a cross-disorder mega-analysis. Also, the heterogeneity factors such as onset age and severity of the psychiatric and neurological conditions may have influences on the observed case-control differences. For instance, greater cortical differences could be observed in recurrent than first-episode patients, which may contribute to the non-significant correlation of the latter group’s effect with PC1. Therefore, the utility of PC1 in characterizing a global pattern of abnormalities in psychiatric disorders will need to be tested in future studies with heterogenous disease groups.
