With the advent of whole-exome sequencing, Tatton-Brown et al. and Gibson et al. traced the molecular etiology of Weaver syndrome to heterozygous pathogenic variants in EZH2, which encodes the primary H3K27 methyltransferase and core component of the Polycomb repressive complex 2 (PRC2) (14, 15). This evidence concerns the gene EZH2 and Weaver syndrome.