Alternative modes of investigation, such as network medicine, are needed to further our understanding of the roles of pathways in complex biological traits. 138 If polygenicity is indeed fundamental to complex psychiatric disorders and if some psychiatric disorders eventually prove to be pathway diseases, 137 then we need to confront this directly and to develop innovative methods. Developing such methods is more constructive and more likely to advance our understanding of these devastating diseases than raging against nature for not delivering common diseases in simpler Mendelian units.
