As we continue to consider different causes of criminality, genetics remains largely uncharted territory. In a recent article by Jaakko Lappalainen and colleagues (Linkage of Antisocial Alcoholism to the Serotonin 5-HT1 B Receptor Gene in 2 Populations, Archives in General Psychiatry, 55, 989-994, 1998), however, DNA was linked to antisocial alcoholism. In their study, these investigators used two very different populations to test whether the 5-HT1 B gene is associated with alcoholism characterized by aggressive and impulsive behavior. The first sample was comprised of Finnish male alcoholic criminals and their families (a total of 72 families) and a group of healthy Finnish male volunteers. The second sample included 418 members of an extended Southwestern American Indian family with a high rate of alcoholism. Diagnoses of antisocial and non-antisocial alcoholism and subsequent tests of linkage to the specific gene in question were done using standard methods.

The results indicate that the 5-HT1 B gene is implicated in the etiology of antisocial alcoholism but not of non-antisocial alcoholism: one particular form of the gene was found statistically more frequently in antisocial alcoholics than in non-antisocial alcoholics or in unaffected individuals. The fact that these results were obtained for both populations strengthens the argument that the 5-HT1 B gene is important for the development of this disorder. However, the sample sizes used were small, the populations were very specific and not representative of the general population in many characteristics, and, in the Finnish population, the focus was on males. Replication of these findings by an independent research team testing a more general population is necessary for validation.

While the evidence obtained from this research suggests that the 5-HT1 B gene may be important in the development of antisocial alcoholism in these specific populations, it is important to note that the gene also appears not to be necessary nor sufficient for the development of this disorder. Still, this data may contribute to mitigating criminal responsibility or assessing prognosis of selected defendants.

Lappalainen, J., Long, J.D., Egert, M., Ozaki N., Robin, R., Brown, G., Naukkarinen, H., Virkkunen, M., Linnoila, M., & Goldman, D. (1998). Linkage of Antisocial alcoholism to the serotonin 5-HT1B receptor gene in 2 populations. Arch Gen Psychiatry Vol 55: 989-994.