An alternative to the diathesis–stress framework at the heart of genetic vulnerability thinking is the one which presupposes that it is not so much that individuals vary only in their susceptibility to adversity vis-à-vis psychopathology, but rather that these putatively ‘vulnerable' individuals are actually more susceptible and, thus, responsive to both positive and negative environmental conditions, that is, in a ‘for better and for worse' manner. This differential-susceptibility perspective does not just contend, as many have, that genes are neither inherently good or bad, or even that their developmental and behavioral effects depend on person–environment fit,8, 9 but rather—and distinctively—that individuals vary in their plasticity or susceptibility to environmental influences. Thus, the very genes that seem—in so much psychiatric genetic research—to make individuals disproportionately vulnerable to adversity vis-à-vis psychopathology may, simultaneously, confer on them an advantage when it comes to benefiting from exposure to environmental support or enrichment (for example, nurturance), including just the absence of adversity. Were this the case, it would seem more appropriate to speak of ‘plasticity genes' rather than ‘vulnerability genes' and of highly plastic or
