IN THE ARTICLE by Berman et al,1 in this issue of the ARCHIVES, the authors report that administration of α-methylparatyrosine to subjects with a history of depressive episodes evoked a brief "relapse" of depressive symptoms. In related articles, the authors have reported that healthy subjects without a history of depressive episodes do not display this sensitivity to α-methylparatyrosine.2 The authors' interpretation of these findings is that the behavioral sensitivity of individuals to α-methylparatyrosine may be a "phenotypic trait marker for depression," and useful for identifying individuals who are prone to develop depressive episodes even though they have no current symptoms. If true, such a marker might also be useful for identifying individuals with latent mood disorders during a preclinical phase of their illness. The development of a laboratory test to aid in the diagnosis of individuals with mood disorders would be an important advance in our capacity to treat depression; however, many issues need to be resolved to provide a stronger foundation for the authors' interpretation of their findings.
Csernansky JG, Posener JA. Laboratory Tests to Aid in Psychiatric DiagnosisAre We Making Progress?. Arch Gen Psychiatry. 1999;56(5):405-406. doi:10.1001/archpsyc.56.5.405