Abstract: Non-drug addictions, which are also referred to as behavioral addictions, or non-substance- related addictions, include disorders such as pathological gambling, internet addiction, shopping addiction, cyber game addiction, sex addiction and binge-eating. These disorders are characterized by craving for certain behaviors, impaired impulse controls, tolerance, withdraw and high relapse rates. High phenomenological similarities and comorbidity between non-drug addictions and drug addictions indicate that these two types of addictions may share some common etiological mechanisms. Family and twin studies revealed moderate to large genetic influence on non-drug addictions, such as binge-eating and pathological gambling in male. Molecular genetic studies found that serotonin (5-HT) system genes, dopamine receptor genes and MAOA genes might be involved in the etiology of non-drug addictions. Furthermore, brain activities of non-drug addicts were different from those of the control groups, especially in the neural pathway for reward, cue processing and impulsive control. Investigating the underlying genetic and neurobiological mechanisms of non-drug addictions has both theoretical and practical implications. Studies from multiple perspectives are needed to illustrate the similarities and heterogeneity of the non-drug addictions and drug addictions.

Key words: non-drug addictions, genetics, neurobiological mechanism