Neurobiological and Clinical Markers for a Severe Form of Alcoholism in Women

It is now well established that a person's risk for developing alcoholism(1) tends to reoccur in families (Hill et al. 1977; Cotton 1979; Hill et al. 1987; Hill 1994). Although alcoholism is clearly familial, the role of genetics in a person's vulnerability to develop alcoholism continues to be debated. Most researchers would support the notion that some genetic influence occurs. The question to be asked is: How much of the variation between people in susceptibility to alcoholism is explained by genetic factors? It is also important to ask: How is genetic vulnerability moderated by personal factors (e.g., gender, age, and co-occurring psychiatric disorders) and environmental ones (e.g., cultural milieu and shared familial environment)? This review will discuss the role of genetic factors in the development of alcoholism in women. The data were obtained from the author's large, high-density-for-alcoholism pedigree study(2) of women. The article will discuss (1) the most recent studies of event-related potential(3) differences in women and their offspring and (2) the clinical characteristics of their offspring. EVIDENCE FOR GENETIC MEDIATION IN WOMEN Several types of studies traditionally have been used in attempts to clarify the contribution of genetic influences to alcoholism, including family, adoption, and twin studies. Some of these studies support a genetic role in women's alcoholism. Family Data The first study to investigate the familial transmission of alcoholism separately for men and women alcoholics was completed by Cloninger and colleagues (1978). Applying a model (of transmission) that included both genetic and environmental factors, Cloninger and colleagues (1978) concluded that the difference in alcoholism prevalence observed between men and women resulted entirely from cultural or nonfamilial environmental factors. Based on the most recent epidemiological data, the ratio of male to female alcoholism is 2:1 in the general population (Kessler et al. 1994). Cloninger and colleagues found that equal numbers of alcoholic relatives were counted among both male and female alcoholics in their early study, suggesting that both genders have an equal likelihood that their disorder is inherited or is genetically mediated. Adoption Studies In further support of alcoholism's familial nature, one line of research has indicated that the disease is more likely to be transmitted within families than are most psychiatric disorders (Merikangas et al. 1985). This high transmissibility could, however, result from the family environment (e.g., exposure to an alcoholic parent) rather than from genetic factors. In seeking to separate these two possible influences, a now-classic study of adopted children that concerned the etiology of alcoholism in men (Goodwin et al. 1973) suggested that transmission can occur even in the absence of exposure to an alcoholic parent. Few adoption studies have been conducted that address genetic factors in women's alcoholism. Thus, the conclusions that can be reached about genetic transmission based on adoption studies in women are tentative (Hill and Smith 1991; Hill 1993). Three adoption studies have been conducted that report results for female adoptees, one each in Sweden (Bohman et al. 1981), Denmark (Goodwin et al. 1977), and the United States (Cadoret et al. 1985). The Swedish and Danish studies found too few alcoholic women to warrant any conclusions. However, Cadoret and colleagues (1985) had a sufficiently large sample to conclude that genetic factors operated in the etiology of female alcoholism (for further discussion of adoption research, see the article by Cadoret, pp. 195-200). Twin Studies Further evidence for the genetic mediation of alcoholism in women can be gained from studies that have examined whether members of adult twin pairs match their twins in alcohol-related behaviors. This research compares the agreement in behavior between members of identical twin pairs (i. …