The genome-wide supported microRNA-137 variant predicts phenotypic heterogeneity within schizophrenia

Area of Science:

• Neuroscience
• Genetics
• Psychiatry

Background:

• Schizophrenia exhibits significant phenotypic variability.
• Genetic factors, including the MIR137 gene, play a role in schizophrenia.
• The rs1625579 variant near MIR137 is a genome-wide significant risk factor.

Purpose of the Study:

• To investigate the influence of the MIR137 risk variant rs1625579 on schizophrenia.
• To examine the impact of this variant on age-at-onset of psychosis and brain structure.

Main Methods:

• Analysis of four independent schizophrenia patient samples (n=510) for age-at-onset.
• Neuroimaging (MRI) in an imaging-genetics subsample (n=213) including controls.
• Assessment of white matter integrity, hippocampal volume, and lateral ventricular size.

Main Results:

• The MIR137 risk genotype significantly predicts earlier age-at-onset of psychosis.
• Patients with the risk genotype showed reduced white matter integrity, smaller hippocampi, and larger lateral ventricles.
• Individuals with the protective allele did not differ from controls in brain structure.

Conclusions:

• The MIR137 gene substantially influences phenotypic variability in schizophrenia.
• This genetic influence impacts key factors related to clinical outcome and treatment response.
• Genetic risk factor consequences may differ between schizophrenia patients and healthy controls.