Integrative GWAS identifies novel loci and genetic links between psychiatric and metabolic factors in anorexia nervosa.
📄 Abstract
Anorexia nervosa (AN) is a complex psychiatric disorder with both psychiatric and metabolic underpinnings. This study aims to explore the genetic architecture of AN and the interplay between its psychiatric and metabolic components. Through a meta-analysis of AN GWAS data from European and Finnish populations, we identified a novel genome-wide significant locus near the SOX5 gene. Genetic correlation and Mendelian randomization analyses revealed shared and potentially causal relationships between AN and multiple psychiatric and metabolic traits. Local genetic correlation analysis identified 185 significant genomic regions contributing to shared heritability between AN and correlated phenotypes, with 100 loci demonstrating pleiotropic effects across multiple traits. The MTAG analyses identified 86 significant loci (34 overlapping with local genetic correlation results), including 25 novel loci such as brain-relevant VAMP2 (17p13.1) and metabolic-neurological hubs LPL (8p21.3) and BDNF (11p14.1). Gene Co-expression Network Analysis (WGCNA) further identified key gene modules associated with both metabolic and neurological pathways, particularly highlighting synaptic signaling and lipid metabolism. Single-cell transcriptomic analysis further resolved this genetic risk to the cellular level, confirming its concentration in limbic and striatal GABAergic neurons and extending the implicated circuitry to include cortical regions involved in motor function. These findings collectively demonstrate the intricate genetic interplay between psychiatric and metabolic pathways in AN, underscoring the necessity of an integrated approach to understanding its pathogenesis.