Unaltered empathy-related behaviors in Williams–Beuren syndrome mouse models

Williams-Beuren Syndrome (WBS), a neurodevelopmental disorder caused by a heterozygous microdeletion at chromosome 7q11.23, is characterized by hypersociability and enhanced affective empathy. However, the specific genetic and neural mechanisms within the WBS locus underlying this elevated empathic response remain unknown. Here, we investigated empathy-related behaviors, including observational fear and allogrooming, in WBS mouse models harboring a deletion within the conserved syntenic region on mouse chromosome 5. We demonstrate that WBS mice exhibited emotional contagion and prosocial consolation behaviors comparable to their wild-type controls. Furthermore, WBS mice with single-gene deletions of the cortex-enriched genes Abhd11, Limk1, Mlxipl, and Stx1a also showed unaffected empathic freezing behavior. Collectively, our findings suggest that the enhanced empathic responsiveness reported in individuals with WBS may be influenced by reduced social inhibition toward others, while acknowledging that limitations of current rodent behavioral assays preclude definitive conclusions regarding primary neural mechanisms of empathy.