The lack of female subjects was due to the ambiguous expression of the MAOA genotype in females, but the failure to include minorities was based on the fact that prior research had focused on Caucasian samples. Future research needs to be more inclusive. Conclusion

Several studies have attempted to examine the causes of antisocial personality disorder. As the above three cases highlight, it is relatively simple to determine factors that are linked to antisocial behavior, but much more difficult to label any of those factors as a cause of antisocial disorder. To truly determine causation, one would need to conduct a truly random study using child subjects, and, given the nature of those lifestyle factors believed to impact the development of antisocial personality disorder, subject those children to significant trauma. Obviously, such an experiment would be unethical. Therefore, while it may be impossible to ever conclusively determine the cause of antisocial personality disorder, researchers can continue to try to uncover factors that are likely to contribute to the expression of antisocial behaviors in the adult population. The...

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