Objective: Circular RNA (circRNA) molecules may play a significant role
in the pathogenesis of psychiatric disorders by regulating synaptic gene
expression. This study aimed to evaluate the relationship between the
peripheral expression levels of three circRNA molecules (chr3_196488683,
chr5_69175537, and hsa_circ_0084021) and clinical characteristics,
specifically behavioral phenotypes related to self-harm and harm to others,
in individuals diagnosed with schizophrenia and schizoaffective disorder.
Methods: The study included 104 patients aged 18–65 diagnosed with
schizophrenia or schizoaffective disorder. RNA was isolated from peripheral
blood, and circRNA molecules were identified using RNA sequencing
techniques. Clinical status was assessed using the Positive and Negative
Syndrome Scale, Clinical Global Impressions Scale, Global Assessment of
Functioning, Calgary Depression Scale for Schizophrenia, Beck Anxiety
Inventory, Beck Scale for Suicide Ideation, and Suicide Probability Scale.
The relationship between concurrent circRNA levels and clinical features
was investigated.
Results: A significant positive correlation was observed among the
circRNAs (p<0.001). Apart from a weak positive correlation between
chr3_196488683 and the Beck Anxiety Inventory score (r=0.213,
p=0.03), no significant relationship was found between clinical scales and
circRNAs. No significant difference was detected between groups regarding
suicidal behavior. However, mean levels of all circRNAs were found to be
statistically significantly higher in the group with self-injurious behavior
(chr3_196488683, p=0.036; chr5_69175537, p=0.001; hsa_circ_0084021,
p=0.045). Similarly, levels of chr3_196488683 and chr5_69175537 were
significantly higher in the group with homicidal behavior (p<0.001).
Conclusion: The findings suggest that peripheral circRNA levels may be
associated with anxiety and behavioral risk profiles involving harm to self or
others, indicating their potential value as biomarkers.
Keywords: Homicidal behaviour, circular RNA, self-injurious behaviour,
schizoaffective disorder, schizophrenia, suicidal behaviour