The question of nature versus nurture has been at the center of many debates, especially within the discipline of psychological sciences. This article will examine existing views regarding the importance of contributions to addiction risk, in particular, genetic (nature) versus environmental (nurture) contributions, through a review of existing literature. The nature-based view is that expression of addiction (phenotype) is based on genetic predisposition (genotype). Numerous genetic pedigree studies have been conducted over the years. Most findings from these studies indicate that monozygotic twins have greater concordance of dependency than dizygotic twins. More specifically, the more genes are shared, the more similar the propensity for addiction. The first genetic studies of addiction were family-based, which provided some initial clues to the potential heritability of addictive disorders by examining the risk of first-degree substance abuse disorders. relatives of individuals who had a substance use disorder or no substance use disorder. A study was conducted by Bierut et al. (1998), who produced results indicating that, compared to a control individual, siblings of alcohol-dependent probands had elevated rates of alcohol dependence. However, family models cannot distinguish whether the cause of family resemblance is genetic or environmental. Adoption studies have also been used in genetics-related addiction research. Adoption studies involve comparing concordance and correlation between offspring behavior (e.g. alcohol dependence) and characteristics of both biological and adoptive parents. Similarity observed between the o... half of the card... the victims. Child Abuse Negl, 21, 529–539. McGue, M. (1999). The behavioral genetics of alcoholism. Curr Dir Psychol Sci, 8, 109–115. McGowan-Anderson, L. J. (2006). Genetic predisposition: is the human organism predisposed to addictive disorders? Journal of Addictive Disorders. Retrieved from http://www.breining.edu.Mullings, J.L., Hartley, D.J., & Marquart, J.W. (2004). Exploring the relationship between alcohol use, childhood maltreatment, and treatment needs among female prisoners. Replace Misuse, 39, 277–305. Newcomb, M. D., Bentler, P. M. (1988). Impact of adolescent drug use and social support on young adult problems: A longitudinal study. J Abnorm Psychology, 97, 64–75. Osler, M., Nordentoft, M., & Andersen, A. M. (2006). Childhood social environment and risk of drug and alcohol abuse in a group of Danish men born in 1953. Am J Epidemiol, 163, 654–661.