Family genetic risk scores for four major psychiatric disorders are closely associated with patients' diagnostic trajectories, according to a study in this week's JAMA Psychiatry. Diagnostic stability and familial and/or genetic risk have long been among the most important psychiatric nosologic validators. To investigate the interrelationships of family genetic risk scores with diagnostic stability or diagnostic change in major depression, bipolar disorder, other nonaffective psychosis, and schizophrenia, a group led by Virginia Commonwealth University researchers examined a population-based cohort of 269,097 Swedish individuals, examining incident and final diagnoses of these four disorders over a mean of 13 years. They found that a high genetic risk for the incident diagnosis was associated with diagnostic stability, while high genetic risk for the final diagnosis and low genetic risk for the incident diagnosis was associated with diagnostic change. "Our findings demonstrate the added value of studying patients a decade into their course of illness, as genetic studies of incident cases would produce considerably noisier findings, including higher cross-disorder genetic correlations," the study's authors conclude.