These paradoxical findings are consistent with several hypotheses. One is that East Asians fail to acknowledge symptoms of mental illness because of social stigma and potential “loss of face” [42–47] or because the stoicism associated with Chinese culture encourages individuals to tolerate emotional difficulties rather than seek help [48, 49]. A second related hypothesis is that East Asians have a greater tendency toward somatization of psychiatric symptoms, in part because they may not view psychiatric symptoms as signs of illness [48–50]. A third contention is that the strong family and social networks in East Asian societies buffer individuals from the potentially negative impacts of stressful events [16, 48, 49, 51]. An extension of this argument posits a coevolution of 5-HTTLPR and collectivist cultures–East Asia, for example–in which values of social harmony and support act as buffers to reduce stress and resultant affective disorders among genetically susceptible populations [52]. A final hypothesis is that these differences arise from ethnic variation in the phenotypes associated with the 5-HTTLPR polymorphism.
