Alcohol abuse and criminality : a cross-fostering study of gene-environment interaction

Sammanfattning: The subjects consists of all persons born out of wedlock in Stockholm during the years 1930 through 1949 and who were placed in non-related adoptive homes by the age of three years (N = 1 753, or 862 men and 913 women).Data are obtained from official records.Results. Alcohol abuse cannot be regarded as a homogeneous trait distributed in the population according to one single dimension — severity. Rather two types of alcohol abuse was demonstrated in this cohort. Type 1 abuse, accounting for about 75 % of registered abuse covered the entire range from mild to severe abuse. Provided that there was a genetic predisposition to that type of abuse, the severity in expression was mainly determined by environmental factors. Type 2 abuse, on the other hand, was highly heritable over the entire range of social backgrounds. Given the predisposition to that type of abuse, the risk was increased ninefold in the adopted away sons regardless of postnatal influences.There were clear sex-differences concerning alcohol abuse. Type 1 abuse was common in both men and women whereas type 2 abuse was transmitted primarily from fathers to sons. Also as regards type 1 abuse, men and women reacted differently to postnatal stress.Different genetic and environmental antecedents influenced the development of criminality depending on whether or not there was associated alcohol abuse. The analyses indicated that most registered criminality, especially severe and recidivistic forms, were secondary to alcohol abuse.Adoptees registered for criminality but not for alcohol abuse had usually com­mitted only a small number of petty offences. Their biological parents were also characterized by petty criminality and little alcohol abuse.In conclusion, the results demonstrated genetic heterogeneity, sex-specificity, and heterogeneity in postnatal antecedents in the development of alcohol abuse and criminality. This means that unittary definitions and models of alcohol abuse and criminality have outlived their utility. In the case of alcohol abuse a first prere­quisite is an inborn ability to drink to such an extent that it gives rise to social or medical problems. Apparently, not all people seem to have this ability. All evidence indicates that genetic factors play an important role in this inability. Secondly, among those people who are able to drink alcoholic beverages there may be genetically determined differences, for instance, some people may be more prone to develop dependence than others.Implications. Alcohol abuse can indirectly be prented by changing environmental conditions that increase the risk. Any plans, however, that are directly aimed at decreasing alcohol abuse must primarily focus on the reduction of the distribution and consumption of alcohol as well as on changes in drinking habits. Concerning criminality, the only implication that seems to be firmly warranted is that prevention of alcohol abuse will result in a reduction of criminality, especially of recurrent and severe forms. If genetic factors can indeed be shown contribute to liability to criminality, the ancient and venerable jurisprudence of society, resting on the concept of penalty and penance, will appear utterly out- of-date and primitive.