Menkes disease is the most clinically severe disease on an allelic spectrum of ATP7A-related disorders, which includes occipital horn syndrome (OHS; MIM 304150), and X-linked distal spinal muscular atrophy type 3 (SMAX3; MIM 300489) (Fradin et al., 2020; Zlatic et al., 2015). Here, ATP7A is linked to occipital horn syndrome.