Variants in additional cohesin-associated proteins like MAU2, STAG1, and STAG2 have been associated with CdLS or phenotypes reminiscent of CdLS in few individuals (Lehalle et al., 2017; Mullegama et al., 2017; Soardi et al., 2017; Yuan et al., 2019; Parenti et al., 2020). Here, STAG1 is linked to Cornelia de Lange syndrome.