KMT2A variants are reported also in one Coffin–Siris (CSS) patient (pt #K2431 in Bramswig et al. [20]), in two Cornelia de Lange syndrome (CdLS) patients (Yuan et al. [21], patient CdLS #3 and Parenti et al. [22], patient #1), in two patients with a diagnosis of Kabuki syndrome (KS) (patients KS8 and KS29 in Sobreira et al. [23]) and in another RSTS-like patient from our previous cohort (Negri et al. [24], pt #103). Here, KMT2A is linked to Coffin-Siris syndrome.