KS patients negative for mutations in KMT2D or KMD6A were found carriers of pathogenic variants in genes related to WDSTS, KLEFS, Mental Retardation Autosomal Dominant 23 (MRD23, OMIM #615761), Say-Barber-Biesecker-Young-Simpson or Ohdo syndrome (SBBYSS, OMIM #603736), Coffin-Siris syndrome-4 (CSS4, OMIM #614609), Floating Harbor syndrome (FLHS, OMIM #136140), CHARGE syndrome (CHARGE, OMIM #214800) and LLS (e.g. pts GDB1054, GDB1405, GDB1400, #18–2,261, GDB1128, GDB1185, GDB1311, GDB1404, GDB1422, GDB1154, GDB1406, GDB1433 in (Squeo et al., 2020)). This evidence concerns the gene KMT2D and Floating-Harbor syndrome.