STAG2 and Global developmental delay: Recently, we described the first reported de novo heterozygous loss‐of‐function variants in the X‐linked Stromal Antigen 2 (STAG2, OMIM: 300826) gene, in three females with common phenotypes including microcephaly, microtia, hearing loss, developmental delay, dysmorphic features, language delay, congenital heart defect, and clinodactyly of the 5th finger (Mullegama et al., 2017).