The present study examines the link between methylation of the BDNF gene promoter region and patterns of neural activity that are associated with maternal response to stressful versus non-stressful child stimuli within a sample consisting of mothers with interpersonal violence-related PTSD (IPV-PTSD) that is above-threshold and sub-threshold for DSM-IV-TR diagnosis as well as non-PTSD control-mothers. This evidence concerns the gene BDNF and post-traumatic stress disorder.