SNORD3C, a blood biomarker associated to suicide attempts in patients with anorexia nervosa.

Anorexia nervosa (AN) is a psychiatric disorder with a high heritability (h2∼70%). Despite extensive meta-analysis of genome-wide association studies, the molecular mechanisms underlying genetics of AN and its complications, particularly suicidal behavior, remain unclear. We performed mRNA sequencing on peripheral blood mononuclear cells from 15 patients with AN (5 with a lifetime history of suicide attempts and 10 without). After correcting for multiple testing, we identified dysregulation of several genes, and confirmed our findings in an independent cohort of 34 patients with AN. Our analysis revealed significant dysregulation of several genes, including SNORD3C, which is implicated in vitamin D metabolism. These genes were enriched in RNA metabolism and innate immune pathways. The presence of these dysregulated genes was associated with suicidal behavior in patients with AN. Our findings suggest that SNORD3C and other differentially expressed genes may serve as potential biomarkers for suicidal risk in AN. This study enhances our understanding of the biological pathways involved in the pathogenesis of suicidal behavior in AN, paving the way for future research and potential clinical applications.