This is of particular significance in the study of anxiety disorders, since the prevalence of anxiety disorders in the general population is twice as high in women compared to men (Bandelow and Michaelis, 2015) and sex-dependent effects on anxiety and stress-vulnerability have been found in Mecp2-deficient mice (Philippe et al., 2018; Cosentino et al., 2021). Here, MECP2 is linked to anxiety disorder.