Objective: The Schizophrenia Psychiatric Genome-wide Association (GWAS) Consortium recently reported on five novel schizophrenia susceptibility loci. The most significant finding mapped to a micro-RNA, MIR-137, which may be involved in regulating the function of other schizophrenia and bipolar disorder susceptibility genes. Method: We genotyped 821 patients with confirmed DSM-IV diagnoses of schizophrenia, bipolar affective disorder I and schizoaffective disorder for the risk SNP (rs1625579) and investigated the clinical profiles of risk allele carriers using a within-case design. We also assessed neurocognitive performance in a subset of cases (n=399) and controls (n=171). Results: Carriers of the risk allele had lower scores for an OPCRIT-derived positive symptom factor (p=0.04) and lower scores on a lifetime measure of psychosis incongruity (p=0.017). Risk allele carriers also had more cognitive deficits involving episodic memory and attentional control. Conclusion: This is the first evidence that the MIR-137 risk variant may be associated with a specific subgroup of psychosis patients. Although the effect of this single SNP was not clinically relevant, investigation of the impact of carrying multiple risk SNPs in the MIR-137 regulatory network on diagnosis and illness profile may be warranted.
Cummings, E., Donohoe, G., Hargreaves, A., Moore, S., Fahey, C., Dinan, T. G., McDonald, C., O'Callaghan, E., O'Neill, F. A., Waddington, J. L., Murphy, K. C., Morris, D. W., Gill, M., & Corvin, A. (2013). Mood congruent psychotic symptoms and specific cognitive deficits in carriers of the novel schizophrenia risk variant at MIR-137. Neuroscience Letters, 532(1), 33-38. https://doi.org/10.1016/j.neulet.2012.08.065