Here, we relate αα-hub stability to function by structural and thermodynamic studies of the Sin3A-paired amphipathic helix 1 (PAH1) wt hub domain and two predicted loss-of-function variants (A126V and K155E) found in patients with the neurodevelopmental Witteveen-Kolk syndrome. This evidence concerns the gene SIN3A and 15q24 microdeletion syndrome.