Gambling Disorders: A Focus on Genetic Aspects

This chapter provides an overview and discusses findings from genetic studies conducted on pathological gambling. Twin studies have found that: (1) the heritability of pathological gambling is estimated to be approximately 50% for both males and females; (2) pathological gambling and subclinical pathological gambling are a continuum of the same disorder; (3) pathological gambling shares genetic vulnerability factors with antisocial behaviors, alcohol dependence, and major depressive disorder; and (4) genetic factors underlie the association between exposure to traumatic life events and pathological gambling. Molecular genetic investigations on pathological gambling are at an early stage and published studies have reported associations with genes involved in the brain's reward and impulse control systems, as well as with genes in addiction-related pathways. Despite the paucity of studies in this area, published studies have provided considerable evidence of the influence of genetic factors in pathological gambling and its complex interaction with other psychiatric disorders and environmental factors. The next step would be to investigate the association and interaction of these variables in larger molecular genetic studies with subphenotypes that underlie the disorder.