NFASC and psychiatric disorder: 2024), suggesting shared pathophysiological mechanisms across psychiatric disorders. NFASC, critical for axon guidance and node of Ranvier formation (Wang et al. 2022; Ghosh et al. 2018; Song et al. 2023), has been implicated in neurodevelopmental disorders with peripheral demyelination (Dong et al. 2022). The observed inverse association between NFASC and BD aligns with emerging evidence linking axonal integrity deficits to mood dysregulation (Efthymiou et al. 2019; Sherman et al. 2005).