VNN1 : a new biomarker of anorexia nervosa
Anorexia nervosa (AN) is a psychiatric disorder with an estimated heritability of around 70%. Although the largest genome-wide association study meta-analysis on AN identified independent loci-conferring risk to the disorder, the molecular mechanisms underlying the genetic basis of AN remains to be elucidated. To explore AN, we ran a transcriptome profiling in peripheral blood mononuclear cells of 15 AN subjects and 15 healthy controls. We validated our mean results in a mouse model of chronic food restriction mimicking several aspects of AN. Through this exploratory study we identified 673 significantly differentially expressed genes in AN. Among these genes, we identified the Vanin-1 (Vnn1) gene that appears to play a major role in the regulation of multiple metabolic pathways. We confirmed an underexpression of Vnn1, especially in the liver, in a mouse model of chronic food restriction. These results indicate that quantitative food restriction affects Vnn1 expression, suggesting that this gene may contribute to the anorexic phenotype in the chronic food restriction mouse model as well as in patients affected by AN. We believe that this report highlights promising candidate genes and gene pathways for AN and reveals Vnn1 as a biomarker that may be used as molecular targets to predict and/or to understand AN. Overall design: All patients with AN were recruited through REMANO protocol. Diagnoses were made according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders 5 (citation), screened through the Mini-International Neuropsychiatric Interview (MINI) during a face-to-face interview with a trained clinician. Exclusion criteria included other non-AN ED and potentially confounding psychiatric diagnoses such as psychotic disorders, and medical or neurological conditions causing weight loss.