Genetic and environmental influences on gambling disorder liability: a replication and combined analysis of two twin studies [subscription access article]

Davis, C., Slutske, W., Martin, N., Agrawal, A., & Lynskey, M. (n.d.).  Psychological Medicine, 1(8). doi:10.1017/S0033291718002325

Background: Gambling disorder (GD), recognized in Diagnostic and Statistical Manual of Mental Disorders, Version 5 (DSM-5) as a behavioral addiction, is associated with a range of adverse outcomes. However, there has been little research on the genetic and environmental influences on the development of this disorder. This study reports results from the largest twin study of GD conducted to date.

Methods: Replication and combined analyses were based on samples of 3292 (mean age 31.8, born 1972–79) and 4764 (mean age 37.7, born 1964–71) male, female, and unlike-sex twin pairs from the Australian Twin Registry. Univariate biometric twin models estimated the proportion of variation in the latent GD liability that could be attributed to genetic, shared environmental, and unique environmental factors, and whether these differed quantitatively or qualitatively for men and women.

Results: In the replication study, when using a lower GD threshold, there was evidence for significant genetic (60%; 95% confidence interval (CI) 45–76%) and unique environmental (40%; 95% CI 24–56%), but not shared environmental contributions (0%; 95% CI 0–0%) to GD liability; this did not significantly differ from the original study. In the combined analysis, higher GD thresholds (such as one consistent with DSM-5 GD) and a multiple threshold definitions of GD yielded similar results. There was no evidence for quantitative or qualitative sex differences in the liability for GD.

Conclusions: Twin studies of GD are few in number but they tell a remarkably similar story: substantial genetic and unique environmental influences, with no evidence for shared environmental contributions or sex differences in GD liability. Article details and access conditions


Genetic Aspects of Gambling Disorders: Recent Developments and Future Directions – Springer

The familial aggregation of gambling disorders has been documented in the literature since the late 1980s. Currently, studies in large twin samples have confirmed that genetic factors contribute to the development of gambling disorders. In comparison to other psychiatric disorders, molecular genetic studies on gambling disorders are at an early stage; however, the use of larger samples and of new methodologies has provided important insights into its genetic underpinnings. The purpose of this article is to review twin and molecular genetics studies on gambling disorders published in the past 5 years and to discuss possible future directions of research in this area…

Source: Lobo, D. S. S. (2016). Genetic Aspects of Gambling Disorders: Recent Developments and Future Directions. Current Behavioral Neuroscience Reports, 1–9.