In This Issue

Gene expression can be down-regulated by methylation of DNA sequences in the gene’s regulatory regions. Such methylation has been related to the effects of early trauma. Yehuda et al. (CME, p. 872) found a transgenerational effect. Adult children of fathers with Holocaust experience and posttraumatic stress disorder (PTSD) had greater methylation of a promoter region in the glucocorticoid receptor gene than did comparison offspring. However, offspring with both maternal and paternal history of Holocaust PTSD had lower than normal methylation. Lower methylation was associated with greater postdexamethasone cortisol suppression, a key pathophysiological feature of PTSD hyperresponsiveness. Paternal PTSD was linked to dissociative experiences in offspring. Editorialist Spiegel (p. 811) discusses the importance of recognizing the new DSM-5 dissociative subtype of PTSD.

Abstinent alcohol-dependent patients have lower dopamine transmission in the prefrontal cortex and other cortical regions than do healthy subjects. The findings of Narendran et al. (p. 881) with positron emission tomography (PET) are consistent with previous anatomical associations for anhedonia, decreased reward sensitivity, and impaired executive functioning. The study’s innovative PET methods, predicts Smith in an editorial (p. 814), will pave the way for greater targeting of alcoholism treatments to dopaminergic systems.

Abnormalities of brain structure related to childhood abuse or neglect are apparent from a whole-brain meta-analysis. Lim et al. (p. 854) included 12 studies comparing a total of 331 children or adults exposed to childhood maltreatment with unexposed individuals. Those with early maltreatment had gray matter abnormalities in the orbitofrontal-temporo-limbic regions, which govern affect, and in the left inferior frontal gyrus, which controls cognitive functioning.