Rare Genetic Variation among Individuals Enrolled in an Early Psychosis Intervention Program

Although many genetic disorders known to be associated with the development of psychosis have been well-characterized, little is known about how common such diagnoses are among patients receiving care through Early Psychosis Intervention Programs in the real world, and what, if any, impact their identification has on the clinical care provided in this context. As such, this observational, retrospective study, which took place in Calgary, Alberta, Canada, sought to explore the spectrum of rare genetic variants harbored by individuals enrolled in an early psychosis program, with a particular focus on the circumstances surrounding why a genetic explanation was suspected, how a diagnosis was made, and any resultant clinical implications. Charts of 899 patients were screened. Thirteen individuals were documented to have at least one rare variant of possible or likely clinical significance. Five individuals' variants were thought to be pathogenic and likely contributed to the development of their psychotic illness, whereas an association (direct or otherwise) was plausible but speculative in eight cases. One additional patient's variant was thought to be non-contributory. Owing to a variety of suggestive phenotypic features, a genetic etiology was first suspected by psychiatry in seven cases, with consequent implications in five of these. The results demonstrate that a small subset of individuals supported by Early Psychosis Intervention Programs may have one or more clinically relevant genetic variants, underscoring the need for psychiatrists working in such settings to consider this possibility and, where appropriate, pursue relevant testing and/or a referral to medical genetics.