Dissociative disorders are a group of mental disorders characterized by a loss of normal integration of psychological and motor function in response to stress or trauma. The familial nature of these disorders has been recognized for over half a century, but it is only in the last two decades that molecular genetic methods have been applied to the study of these disorders. Association studies based on the candidate approach suggested that these disorders were linked to alterations in monoaminergic neurotransmission and in the functioning of the hypothalamic-pituitary-adrenal axis. Research involving newer genetic methods, such as genome-wide association studies and studies of the epigenetic modification of gene expression, have found evidence of links between dissociation and a wide array of genes involved in brain development, synaptic information processing, stress sensitivity, and immune-inflammatory function. Genetic research has also supported the clinical observation of an intimate link between mood, anxiety, trauma-related, and dissociative disorders. Certain limitations of this research, particularly in terms of defining dissociative phenotypes, must be acknowledged. Nevertheless, this research provides valuable leads on the contributions of genetic factors to the pathophysiology of dissociative disorders, and their interaction with both past and current stressors.