Notably, previous studies have identified clinical and molecular similarities between SHMS and disorders associated with variants in PACS2 (DEE66; OMIM #618067) and WDR37 (NOCGUS; OMIM #618652) [24,25,26], suggesting the existence of a PACS1–PACS2–WDR37 axis that may underlie shared phenotypic features across their respective syndromes. Here, PACS1 is linked to Schuurs-Hoeijmakers syndrome.