Contributions of the glucocorticoid receptor polymorphism (Bcl1) and childhood abuse to risk of bulimia nervosa.

This study evaluated the hypothesis that traumatic stress can increase risk of bulimia nervosa (BN) in individuals who are genetically disposed towards lower modulation of physiological stress reactions. We explored the extent to which childhood abuse (physical or sexual), variants of a main glucocorticoid receptor (GR) polymorphism (Bcl1), or their interaction, differentiated women with and without BN. Women seeking treatment for BN (N=129) and non-eating-disordered comparison women (N=98) provided blood samples for assays of the Bcl1 polymorphism, and completed structured interviews assessing eating symptoms, psychiatric symptoms and childhood abuse. Compared to normal-eaters, bulimic women were significantly more likely to carry the low-function Bcl1 C allele (CC or CG genotypes), to report a history of childhood abuse and, more importantly, to be positive for both factors. We interpret our findings as indicating that traumatic stress, when impacting individuals disposed to lower GR modulation, can be etiological for BN.